{"id":107482,"date":"2026-09-19T19:56:42","date_gmt":"2026-09-19T11:56:42","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/107482.html"},"modified":"2026-09-19T19:56:42","modified_gmt":"2026-09-19T11:56:42","slug":"%e4%b8%ba%e4%bb%80%e4%b9%88%e9%9d%a2%e8%af%95%e5%ae%98%e6%80%bb%e7%88%b1%e9%97%aejava%e4%b8%ad%e6%80%8e%e4%b9%88%e5%88%a4%e6%96%ad%e4%b8%a4%e4%b8%aa%e5%af%b9%e8%b1%a1%e6%98%af%e7%9b%b8%e5%90%8c","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/107482.html","title":{"rendered":"\u4e3a\u4ec0\u4e48\u9762\u8bd5\u5b98\u603b\u7231\u95eeJava\u4e2d\u600e\u4e48\u5224\u65ad\u4e24\u4e2a\u5bf9\u8c61\u662f\u76f8\u540c\u7684"},"content":{"rendered":"

\u7b14\u8005\u53bb\u9762\u8bd5\u7684\u65f6\u5019，\u9762\u8bd5\u5b98\u51b7\u4e0d\u4e01\u5730\u95ee\u201cJava\u4e2d\u4e24\u4e2a\u5bf9\u8c61\u600e\u4e48\u5224\u65ad\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u201d，\u7b2c\u4e00\u53cd\u5e94\u5c31\u662f\u7b54：\u7528 equals()\u3002\u8fd9\u4e2a\u56de\u7b54\u4e0d\u80fd\u8bf4\u9519，\u90a3\u8fd8\u9700\u8981\u91cd\u5199\u4ec0\u4e48\u65b9\u6cd5，\u4e3a\u4ec0\u4e48，\u5f88\u5bb9\u6613\u88ab\u7ee7\u7eed\u8ffd\u95ee\u5230\u53d1\u61f5\u3002\u56e0\u4e3a\u9762\u8bd5\u5b98\u771f\u6b63\u60f3\u95ee\u7684\u662f：\u4f60\u8bf4\u7684\u201c\u540c\u4e00\u4e2a\u201d，\u5230\u5e95\u662f\u5730\u5740\u4e00\u6837\u3001\u5185\u5bb9\u4e00\u6837，\u8fd8\u662f\u653e\u8fdb HashMap \u91cc\u4e5f\u80fd\u88ab\u5f53\u6210\u540c\u4e00\u4e2a key？<\/p>\n

\u4e00\u53e5\u8bdd\u7ed3\u8bba： == \u50cf\u662f\u5728\u95ee\u201c\u662f\u4e0d\u662f\u540c\u4e00\u5f20\u8eab\u4efd\u8bc1\u539f\u4ef6\u201d，equals() \u50cf\u662f\u5728\u95ee\u201c\u8eab\u4efd\u8bc1\u4fe1\u606f\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u4eba\u201d，hashCode() \u50cf\u662f\u5728\u95ee\u201c\u5148\u53bb\u54ea\u4e2a\u67dc\u5b50\u91cc\u627e\u8fd9\u4e2a\u4eba\u201d，\u4e09\u8005\u56de\u7b54\u7684\u662f\u4e0d\u540c\u5c42\u6b21\u7684\u95ee\u9898\u3002<\/p>\n

\u8fd9\u7bc7\u4e0d\u5148\u5806\u672f\u8bed\u3002\u6211\u4eec\u5148\u7528\u81ea\u5df1\u7684\u8bdd\u628a\u8fd9\u9053\u9898\u8bb2\u987a，\u518d\u8865\u4e00\u70b9\u6e90\u7801\u548c Android \u91cc\u7684\u5b9e\u9645\u573a\u666f\u3002\u4f60\u53ea\u8981\u8bb0\u4f4f\u4e00\u4e2a\u65b9\u5411：\u5224\u65ad\u5bf9\u8c61\u76f8\u540c，\u5148\u95ee\u6e05\u695a\u4f60\u5230\u5e95\u60f3\u5224\u65ad\u54ea\u79cd\u76f8\u540c\u3002<\/p>\n

1. \u9762\u8bd5\u5b98\u95ee\u201c\u76f8\u540c\u201d，\u5176\u5b9e\u53ef\u80fd\u95ee\u4e09\u4ef6\u4e8b<\/h3>\n

\u6bd4\u5982\u6709\u4e24\u4e2a User：<\/p>\n

User<\/span> a =<\/span> new<\/span> User<\/span>(<\/span>1<\/span>,<\/span> "\u5f20\u4e09"<\/span>)<\/span>;<\/span>
\nUser<\/span> b =<\/span> new<\/span> User<\/span>(<\/span>1<\/span>,<\/span> "\u5f20\u4e09"<\/span>)<\/span>;<\/span><\/p>\n

\u4f60\u8bf4\u5b83\u4fe9\u76f8\u540c\u5417？<\/p>\n

\u8fd9\u4e2a\u95ee\u9898\u8981\u770b\u4f60\u7ad9\u5728\u54ea\u4e2a\u89d2\u5ea6：<\/p>\n\n\u4f60\u60f3\u95ee\u4ec0\u4e48\u600e\u4e48\u53bb\u7406\u89e3Java \u91cc\u5e38\u7528\u4ec0\u4e48<\/tr>\n\n\n\n\n
\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61<\/td>\n\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u4eba\u7ad9\u5728\u8fd9\u91cc<\/td>\na == b<\/td>\n<\/tr>\n
\u5185\u5bb9\u662f\u4e0d\u662f\u4e00\u6837<\/td>\n\u4e24\u5f20\u8868\u4e0a\u7684\u59d3\u540d\u3001id \u662f\u4e0d\u662f\u4e00\u6837<\/td>\na.equals(b)<\/td>\n<\/tr>\n
\u653e\u8fdb\u96c6\u5408\u80fd\u4e0d\u80fd\u5f53\u6210\u540c\u4e00\u4e2a<\/td>\n\u901a\u8baf\u5f55\u91cc\u4f1a\u4e0d\u4f1a\u91cd\u590d\u5b58\u4e24\u4efd<\/td>\nequals() \u52a0 hashCode()<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61<\/p>\n

<\/span><\/p>\n

\u5185\u5bb9\u662f\u4e0d\u662f\u4e00\u6837<\/p>\n

<\/span><\/p>\n

\u96c6\u5408\u91cc\u7b97\u4e0d\u7b97\u540c\u4e00\u4e2a<\/p>\n

<\/span><\/span><\/span><\/span><\/p>\n

\u4e24\u4e2a\u5bf9\u8c61\u662f\u4e0d\u662f\u76f8\u540c<\/p>\n

<\/span><\/p>\n

\u4f60\u95ee\u7684\u662f\u54ea\u79cd\u76f8\u540c<\/p>\n

<\/span><\/p>\n

\u770b\u5f15\u7528：\u7528 ==<\/p>\n

<\/span><\/p>\n

\u770b\u5185\u5bb9：\u7528 equals<\/p>\n

<\/span><\/p>\n

\u770b key：equals \u52a0 hashCode<\/p>\n

<\/span><\/p>\n

\u5148\u8bf4\u6e05\u53e3\u5f84，\u518d\u7ed9\u7b54\u6848<\/p>\n

<\/span><\/p>\n

\u6240\u4ee5\u9762\u8bd5\u65f6\u522b\u6025\u7740\u8bf4\u201c\u7528 equals\u201d\u3002\u66f4\u7a33\u7684\u5f00\u5934\u662f：<\/p>\n

\u8981\u770b\u4f60\u8bf4\u7684\u76f8\u540c\u662f\u54ea\u79cd\u3002\u5982\u679c\u662f\u5224\u65ad\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61，\u7528 ==；\u5982\u679c\u662f\u5224\u65ad\u4e1a\u52a1\u5185\u5bb9\u662f\u4e0d\u662f\u4e00\u6837，\u7528 equals()；\u5982\u679c\u8fd9\u4e2a\u5bf9\u8c61\u8981\u653e\u8fdb HashMap \u6216 HashSet，\u8fd8\u5f97\u4fdd\u8bc1 hashCode() \u548c equals() \u662f\u914d\u5957\u7684\u3002<\/p>\n

\u8fd9\u53e5\u8bdd\u4e00\u8bf4，\u9762\u8bd5\u5b98\u57fa\u672c\u5c31\u77e5\u9053\u4f60\u4e0d\u662f\u53ea\u80cc\u8fc7 API\u3002<\/p>\n

2. ==：\u770b\u7684\u662f\u201c\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61\u201d<\/h3>\n

\u5148\u770b\u6700\u666e\u901a\u7684\u4f8b\u5b50：<\/p>\n

User<\/span> a =<\/span> new<\/span> User<\/span>(<\/span>1<\/span>,<\/span> "\u5f20\u4e09"<\/span>)<\/span>;<\/span>
\nUser<\/span> b =<\/span> new<\/span> User<\/span>(<\/span>1<\/span>,<\/span> "\u5f20\u4e09"<\/span>)<\/span>;<\/span>
\nUser<\/span> c =<\/span> a;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a ==<\/span> b)<\/span>;<\/span> \/\/ false<\/span>
\nSystem<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a ==<\/span> c)<\/span>;<\/span> \/\/ true<\/span><\/p>\n

\u4e3a\u4ec0\u4e48 a == b \u662f false？<\/p>\n

\u56e0\u4e3a new \u4e86\u4e24\u6b21，\u5c31\u50cf\u6253\u5370\u4e86\u4e24\u5f20\u5185\u5bb9\u4e00\u6837\u7684\u8868\u3002\u8868\u4e0a\u7684\u5185\u5bb9\u4e00\u6837，\u4f46\u5b83\u4eec\u4e0d\u662f\u540c\u4e00\u5f20\u7eb8\u3002<\/p>\n

\u4e3a\u4ec0\u4e48 a == c \u662f true？<\/p>\n

\u56e0\u4e3a c = a，\u5c31\u50cf a \u548c c \u90fd\u6307\u7740\u540c\u4e00\u5f20\u7eb8\u3002<\/p>\n

#mermaid-svg-D1494VSFlb6A7aK4{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;fill:#333;}@keyframes edge-animation-frame{from{stroke-dashoffset:0;}}@keyframes dash{to{stroke-dashoffset:0;}}#mermaid-svg-D1494VSFlb6A7aK4 .edge-animation-slow{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 50s linear infinite;stroke-linecap:round;}#mermaid-svg-D1494VSFlb6A7aK4 .edge-animation-fast{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 20s linear infinite;stroke-linecap:round;}#mermaid-svg-D1494VSFlb6A7aK4 .error-icon{fill:#552222;}#mermaid-svg-D1494VSFlb6A7aK4 .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-D1494VSFlb6A7aK4 .edge-thickness-normal{stroke-width:1px;}#mermaid-svg-D1494VSFlb6A7aK4 .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-D1494VSFlb6A7aK4 .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-D1494VSFlb6A7aK4 .edge-thickness-invisible{stroke-width:0;fill:none;}#mermaid-svg-D1494VSFlb6A7aK4 .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-D1494VSFlb6A7aK4 .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-D1494VSFlb6A7aK4 .marker{fill:#333333;stroke:#333333;}#mermaid-svg-D1494VSFlb6A7aK4 .marker.cross{stroke:#333333;}#mermaid-svg-D1494VSFlb6A7aK4 svg{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-D1494VSFlb6A7aK4 p{margin:0;}#mermaid-svg-D1494VSFlb6A7aK4 .label{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;color:#333;}#mermaid-svg-D1494VSFlb6A7aK4 .cluster-label text{fill:#333;}#mermaid-svg-D1494VSFlb6A7aK4 .cluster-label span{color:#333;}#mermaid-svg-D1494VSFlb6A7aK4 .cluster-label span p{background-color:transparent;}#mermaid-svg-D1494VSFlb6A7aK4 .label text,#mermaid-svg-D1494VSFlb6A7aK4 span{fill:#333;color:#333;}#mermaid-svg-D1494VSFlb6A7aK4 .node rect,#mermaid-svg-D1494VSFlb6A7aK4 .node circle,#mermaid-svg-D1494VSFlb6A7aK4 .node ellipse,#mermaid-svg-D1494VSFlb6A7aK4 .node polygon,#mermaid-svg-D1494VSFlb6A7aK4 .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-D1494VSFlb6A7aK4 .rough-node .label text,#mermaid-svg-D1494VSFlb6A7aK4 .node .label text,#mermaid-svg-D1494VSFlb6A7aK4 .image-shape .label,#mermaid-svg-D1494VSFlb6A7aK4 .icon-shape .label{text-anchor:middle;}#mermaid-svg-D1494VSFlb6A7aK4 .node .katex path{fill:#000;stroke:#000;stroke-width:1px;}#mermaid-svg-D1494VSFlb6A7aK4 .rough-node .label,#mermaid-svg-D1494VSFlb6A7aK4 .node .label,#mermaid-svg-D1494VSFlb6A7aK4 .image-shape .label,#mermaid-svg-D1494VSFlb6A7aK4 .icon-shape .label{text-align:center;}#mermaid-svg-D1494VSFlb6A7aK4 .node.clickable{cursor:pointer;}#mermaid-svg-D1494VSFlb6A7aK4 .root .anchor path{fill:#333333!important;stroke-width:0;stroke:#333333;}#mermaid-svg-D1494VSFlb6A7aK4 .arrowheadPath{fill:#333333;}#mermaid-svg-D1494VSFlb6A7aK4 .edgePath .path{stroke:#333333;stroke-width:2.0px;}#mermaid-svg-D1494VSFlb6A7aK4 .flowchart-link{stroke:#333333;fill:none;}#mermaid-svg-D1494VSFlb6A7aK4 .edgeLabel{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-D1494VSFlb6A7aK4 .edgeLabel p{background-color:rgba(232,232,232, 0.8);}#mermaid-svg-D1494VSFlb6A7aK4 .edgeLabel rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-D1494VSFlb6A7aK4 .labelBkg{background-color:rgba(232, 232, 232, 0.5);}#mermaid-svg-D1494VSFlb6A7aK4 .cluster rect{fill:#ffffde;stroke:#aaaa33;stroke-width:1px;}#mermaid-svg-D1494VSFlb6A7aK4 .cluster text{fill:#333;}#mermaid-svg-D1494VSFlb6A7aK4 .cluster span{color:#333;}#mermaid-svg-D1494VSFlb6A7aK4 div.mermaidTooltip{position:absolute;text-align:center;max-width:200px;padding:2px;font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:12px;background:hsl(80, 100%, 96.2745098039%);border:1px solid #aaaa33;border-radius:2px;pointer-events:none;z-index:100;}#mermaid-svg-D1494VSFlb6A7aK4 .flowchartTitleText{text-anchor:middle;font-size:18px;fill:#333;}#mermaid-svg-D1494VSFlb6A7aK4 rect.text{fill:none;stroke-width:0;}#mermaid-svg-D1494VSFlb6A7aK4 .icon-shape,#mermaid-svg-D1494VSFlb6A7aK4 .image-shape{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-D1494VSFlb6A7aK4 .icon-shape p,#mermaid-svg-D1494VSFlb6A7aK4 .image-shape p{background-color:rgba(232,232,232, 0.8);padding:2px;}#mermaid-svg-D1494VSFlb6A7aK4 .icon-shape .label rect,#mermaid-svg-D1494VSFlb6A7aK4 .image-shape .label rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-D1494VSFlb6A7aK4 .label-icon{display:inline-block;height:1em;overflow:visible;vertical-align:-0.125em;}#mermaid-svg-D1494VSFlb6A7aK4 .node .label-icon path{fill:currentColor;stroke:revert;stroke-width:revert;}#mermaid-svg-D1494VSFlb6A7aK4 :root{–mermaid-font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;}<\/p>\n

\u771f\u6b63\u7684\u5bf9\u8c61\u5728\u5806\u91cc<\/p>\n

<\/span><\/p>\n

\u53d8\u91cf\u4fdd\u5b58\u7684\u662f\u5f15\u7528<\/p>\n

<\/span><\/span><\/span><\/span><\/span><\/span><\/p>\n

a<\/p>\n

<\/span><\/p>\n

b<\/p>\n

<\/span><\/p>\n

c<\/p>\n

<\/span><\/p>\n

User \u5bf9\u8c61\u4e00<\/p>\n

<\/span><\/p>\n

User \u5bf9\u8c61\u4e8c<\/p>\n

<\/span><\/p>\n

a \u548c c \u6307\u5411\u540c\u4e00\u4e2a\u5bf9\u8c61<\/p>\n

<\/span><\/p>\n

a \u548c b \u6307\u5411\u4e24\u4e2a\u5bf9\u8c61<\/p>\n

<\/span><\/p>\n

\u4e00\u53e5\u8bdd：<\/p>\n

== \u4e0d\u5173\u5fc3\u5bf9\u8c61\u91cc\u9762\u5199\u4e86\u4ec0\u4e48，\u53ea\u5173\u5fc3\u5de6\u53f3\u4e24\u8fb9\u662f\u4e0d\u662f\u6307\u5411\u540c\u4e00\u4e2a\u5bf9\u8c61\u3002<\/p>\n

3. equals()：\u770b\u7684\u662f\u201c\u4f60\u600e\u4e48\u5b9a\u4e49\u5185\u5bb9\u4e00\u6837\u201d<\/h3>\n

\u90a3 equals() \u5462？<\/p>\n

\u5f88\u591a\u4eba\u4f1a\u8bf4：equals() \u6bd4\u8f83\u5185\u5bb9\u3002<\/p>\n

\u8fd9\u53e5\u8bdd\u53ea\u8bf4\u5bf9\u4e86\u4e00\u534a\u3002\u66f4\u51c6\u786e\u5730\u8bf4：<\/p>\n

equals() \u6bd4\u8f83\u4ec0\u4e48，\u53d6\u51b3\u4e8e\u8fd9\u4e2a\u7c7b\u6709\u6ca1\u6709\u91cd\u5199，\u4ee5\u53ca\u5b83\u91cd\u5199\u65f6\u600e\u4e48\u5199\u3002<\/p>\n

\u9ed8\u8ba4\u60c5\u51b5\u4e0b，\u666e\u901a\u7c7b\u7ee7\u627f\u7684\u662f Object.equals()\u3002\u5b83\u7684\u903b\u8f91\u975e\u5e38\u7b80\u5355：<\/p>\n

public<\/span> boolean<\/span> equals<\/span>(<\/span>Object<\/span> obj)<\/span> {<\/span>
\n return<\/span> this<\/span> ==<\/span> obj;<\/span>
\n}<\/span><\/p>\n

\u4e5f\u5c31\u662f\u8bf4，\u666e\u901a\u7c7b\u5982\u679c\u4e0d\u91cd\u5199 equals()，\u90a3 equals() \u548c == \u51e0\u4e4e\u4e00\u6837，\u8fd8\u662f\u5728\u95ee\u201c\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61\u201d\u3002<\/p>\n

\u6bd4\u5982：<\/p>\n

class<\/span> User<\/span> {<\/span>
\n int<\/span> id;<\/span>
\n String<\/span> name;<\/span><\/p>\n

User<\/span>(<\/span>int<\/span> id,<\/span> String<\/span> name)<\/span> {<\/span>
\n this<\/span>.<\/span>id =<\/span> id;<\/span>
\n this<\/span>.<\/span>name =<\/span> name;<\/span>
\n }<\/span>
\n}<\/span><\/p>\n

User<\/span> a =<\/span> new<\/span> User<\/span>(<\/span>1<\/span>,<\/span> "\u5f20\u4e09"<\/span>)<\/span>;<\/span>
\nUser<\/span> b =<\/span> new<\/span> User<\/span>(<\/span>1<\/span>,<\/span> "\u5f20\u4e09"<\/span>)<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a.<\/span>equals<\/span>(<\/span>b)<\/span>)<\/span>;<\/span> \/\/ false<\/span><\/p>\n

\u4f60\u770b，\u5185\u5bb9\u4e00\u6837，\u4f46\u7ed3\u679c\u8fd8\u662f false\u3002\u56e0\u4e3a User \u6ca1\u6709\u544a\u8bc9 Java：\u201c\u6211\u8ba4\u4e3a id \u4e00\u6837\u5c31\u7b97\u540c\u4e00\u4e2a\u7528\u6237\u3002\u201d<\/p>\n

4. String.equals() \u4e3a\u4ec0\u4e48\u80fd\u6bd4\u8f83\u6587\u5b57\u5185\u5bb9<\/h3>\n

String \u5c31\u4e0d\u4e00\u6837\u4e86\u3002\u5b83\u81ea\u5df1\u91cd\u5199\u4e86 equals()\u3002<\/p>\n

String<\/span> a =<\/span> new<\/span> String<\/span>(<\/span>"hello"<\/span>)<\/span>;<\/span>
\nString<\/span> b =<\/span> new<\/span> String<\/span>(<\/span>"hello"<\/span>)<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a ==<\/span> b)<\/span>;<\/span> \/\/ false<\/span>
\nSystem<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a.<\/span>equals<\/span>(<\/span>b)<\/span>)<\/span>;<\/span> \/\/ true<\/span><\/p>\n

a == b \u662f false，\u56e0\u4e3a\u8fd9\u662f\u4e24\u4e2a\u5bf9\u8c61\u3002<\/p>\n

a.equals(b) \u662f true，\u56e0\u4e3a String.equals() \u6bd4\u8f83\u7684\u662f\u91cc\u9762\u7684\u5b57\u7b26\u662f\u4e0d\u662f\u4e00\u6837\u3002<\/p>\n

\u4f60\u53ef\u4ee5\u628a String.equals() \u60f3\u6210\u8fd9\u6837：<\/p>\n

\/\/ \u7b80\u5316\u7406\u89e3，\u4e0d\u662f\u9010\u884c\u6e90\u7801<\/span>
\nif<\/span> (<\/span>\u4e24\u4e2a\u5f15\u7528\u5c31\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61)<\/span> {<\/span>
\n return<\/span> true<\/span>;<\/span>
\n}<\/span>
\nif<\/span> (<\/span>\u5bf9\u65b9\u4e0d\u662f String<\/span>)<\/span> {<\/span>
\n return<\/span> false<\/span>;<\/span>
\n}<\/span>
\nreturn<\/span> \u4e00\u4e2a\u5b57\u7b26\u4e00\u4e2a\u5b57\u7b26\u6bd4\u8f83;<\/span><\/p>\n

\u6240\u4ee5\u4e0d\u8981\u80cc\u201cequals() \u5c31\u662f\u6bd4\u8f83\u5185\u5bb9\u201d\u3002\u5e94\u8be5\u80cc\u8fd9\u4e2a：<\/p>\n

equals() \u9ed8\u8ba4\u4e0d\u4e00\u5b9a\u6bd4\u8f83\u5185\u5bb9\u3002\u50cf String \u8fd9\u79cd\u7c7b\u662f\u56e0\u4e3a\u5b83\u91cd\u5199\u4e86 equals()，\u6240\u4ee5\u624d\u6bd4\u8f83\u5185\u5bb9\u3002<\/p>\n

5. \u5b57\u7b26\u4e32\u548c\u5305\u88c5\u7c7b\u4e3a\u4ec0\u4e48\u603b\u559c\u6b22\u51fa\u9677\u9631\u9898<\/h3>\n

\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60<\/h4>\n

String<\/span> s1 =<\/span> "hello"<\/span>;<\/span>
\nString<\/span> s2 =<\/span> "hello"<\/span>;<\/span>
\nString<\/span> s3 =<\/span> new<\/span> String<\/span>(<\/span>"hello"<\/span>)<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>s1 ==<\/span> s2)<\/span>;<\/span> \/\/ true<\/span>
\nSystem<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>s1 ==<\/span> s3)<\/span>;<\/span> \/\/ false<\/span>
\nSystem<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>s1.<\/span>equals<\/span>(<\/span>s3)<\/span>)<\/span>;<\/span> \/\/ true<\/span><\/p>\n

\u8fd9\u600e\u4e48\u7406\u89e3？<\/p>\n

"hello" \u8fd9\u79cd\u5b57\u9762\u91cf\u4f1a\u653e\u5230\u5b57\u7b26\u4e32\u5e38\u91cf\u6c60\u91cc\u3002s1 \u548c s2 \u6307\u5411\u540c\u4e00\u4e2a\u6c60\u5b50\u91cc\u7684\u5b57\u7b26\u4e32，\u6240\u4ee5 s1 == s2 \u662f true\u3002<\/p>\n

new String("hello") \u662f\u91cd\u65b0\u521b\u5efa\u4e86\u4e00\u4e2a\u5bf9\u8c61，\u6240\u4ee5 s1 == s3 \u662f false\u3002<\/p>\n

\u4f46\u5b83\u4eec\u6587\u5b57\u5185\u5bb9\u4e00\u6837，\u6240\u4ee5 s1.equals(s3) \u662f true\u3002<\/p>\n

Integer \u7f13\u5b58<\/h4>\n

Integer<\/span> a =<\/span> 127<\/span>;<\/span>
\nInteger<\/span> b =<\/span> 127<\/span>;<\/span>
\nInteger<\/span> c =<\/span> 128<\/span>;<\/span>
\nInteger<\/span> d =<\/span> 128<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a ==<\/span> b)<\/span>;<\/span> \/\/ \u901a\u5e38\u662f true<\/span>
\nSystem<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>c ==<\/span> d)<\/span>;<\/span> \/\/ \u901a\u5e38\u662f false<\/span><\/p>\n

\u8fd9\u4e2a\u5751\u66f4\u5bb9\u6613\u8ba9\u4eba\u8bef\u4f1a\u3002\u5e38\u89c1 JDK \u4f1a\u7f13\u5b58 -128 \u5230 127 \u7684 Integer \u5bf9\u8c61\u3002127 \u547d\u4e2d\u4e86\u7f13\u5b58，\u6240\u4ee5\u4e24\u4e2a\u53d8\u91cf\u53ef\u80fd\u6307\u5411\u540c\u4e00\u4e2a\u5bf9\u8c61；128 \u901a\u5e38\u6ca1\u6709\u547d\u4e2d，\u5c31\u53ef\u80fd\u662f\u4e24\u4e2a\u5bf9\u8c61\u3002<\/p>\n

\u4f46\u7ed3\u8bba\u4e0d\u662f\u201cInteger \u5c0f\u4e8e 128 \u5c31\u7528 ==\u201d\u3002\u7ed3\u8bba\u5e94\u8be5\u662f：<\/p>\n

\u5305\u88c5\u7c7b\u578b\u5224\u65ad\u6570\u503c\u76f8\u7b49，\u522b\u4f9d\u8d56 ==\u3002\u8981\u4e48\u62c6\u6210\u57fa\u672c\u7c7b\u578b\u6bd4\u8f83，\u8981\u4e48\u7528 equals()\u3002<\/p>\n

6. \u5982\u679c\u4f60\u60f3\u8ba9\u4e24\u4e2a User \u5185\u5bb9\u4e00\u6837\u5c31\u7b97\u76f8\u540c，\u8be5\u600e\u4e48\u5199<\/h3>\n

\u5047\u8bbe\u4e1a\u52a1\u91cc\u89c4\u5b9a：\u53ea\u8981 id \u4e00\u6837，\u5c31\u8ba4\u4e3a\u662f\u540c\u4e00\u4e2a\u7528\u6237\u3002<\/p>\n

\u90a3\u4f60\u5c31\u8981\u5728 equals() \u91cc\u5199\u6e05\u695a：<\/p>\n

public<\/span> final<\/span> class<\/span> User<\/span> {<\/span>
\n private<\/span> final<\/span> long<\/span> id;<\/span>
\n private<\/span> final<\/span> String<\/span> name;<\/span><\/p>\n

public<\/span> User<\/span>(<\/span>long<\/span> id,<\/span> String<\/span> name)<\/span> {<\/span>
\n this<\/span>.<\/span>id =<\/span> id;<\/span>
\n this<\/span>.<\/span>name =<\/span> name;<\/span>
\n }<\/span><\/p>\n

@Override<\/span>
\n public<\/span> boolean<\/span> equals<\/span>(<\/span>Object<\/span> obj)<\/span> {<\/span>
\n if<\/span> (<\/span>this<\/span> ==<\/span> obj)<\/span> {<\/span>
\n return<\/span> true<\/span>;<\/span>
\n }<\/span>
\n if<\/span> (<\/span>!<\/span>(<\/span>obj instanceof<\/span> User<\/span>)<\/span>)<\/span> {<\/span>
\n return<\/span> false<\/span>;<\/span>
\n }<\/span>
\n User<\/span> other =<\/span> (<\/span>User<\/span>)<\/span> obj;<\/span>
\n return<\/span> this<\/span>.<\/span>id ==<\/span> other.<\/span>id;<\/span>
\n }<\/span><\/p>\n

@Override<\/span>
\n public<\/span> int<\/span> hashCode<\/span>(<\/span>)<\/span> {<\/span>
\n return<\/span> Long<\/span>.<\/span>hashCode<\/span>(<\/span>id)<\/span>;<\/span>
\n }<\/span>
\n}<\/span><\/p>\n

\u6211\u4eec\u6765\u62c6\u89e3\u4e00\u4e0b：<\/p>\n

\u5982\u679c\u5b83\u4fe9\u672c\u6765\u5c31\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61，\u76f4\u63a5\u8fd4\u56de true\u3002
\n\u5982\u679c\u5bf9\u65b9\u6839\u672c\u4e0d\u662f User，\u76f4\u63a5\u8fd4\u56de false\u3002
\n\u5982\u679c\u5bf9\u65b9\u4e5f\u662f User，\u90a3\u5c31\u6bd4\u8f83 id\u3002
\nid \u4e00\u6837，\u5c31\u5f53\u4f5c\u540c\u4e00\u4e2a\u7528\u6237\u3002<\/p>\n

\u8fd9\u91cc\u6545\u610f\u53ea\u6bd4\u8f83 id，\u6ca1\u6709\u6bd4\u8f83 name\u3002\u56e0\u4e3a\u5f88\u591a\u4e1a\u52a1\u91cc，\u7528\u6237\u6539\u6635\u79f0\u4e4b\u540e，\u4ed6\u8fd8\u662f\u540c\u4e00\u4e2a\u7528\u6237\u3002<\/p>\n

\u8fd9\u5c31\u662f\u9762\u8bd5\u5b98\u559c\u6b22\u8ffd\u95ee\u7684\u5730\u65b9：
\n\u4f60\u4e0d\u662f\u5728\u5199\u4e00\u4e2a\u6b7b\u677f\u516c\u5f0f，\u4f60\u662f\u5728\u5b9a\u4e49\u201c\u4ec0\u4e48\u53eb\u540c\u4e00\u4e2a\u4e1a\u52a1\u5bf9\u8c61\u201d\u3002<\/p>\n

7. \u4e3a\u4ec0\u4e48\u5199\u4e86 equals() \u8fd8\u8981\u5199 hashCode()<\/h3>\n

\u8fd9\u4e00\u6bb5\u662f\u5f88\u591a\u4eba\u771f\u6b63\u6389\u5751\u7684\u5730\u65b9\u3002<\/p>\n

\u5148\u60f3\u4e00\u4e2a\u751f\u6d3b\u4f8b\u5b50：<\/p>\n

\u4f60\u53bb\u5feb\u9012\u67dc\u53d6\u5feb\u9012\u3002\u7cfb\u7edf\u5148\u544a\u8bc9\u4f60：\u53bb 3 \u53f7\u67dc\u3002\u4f60\u53bb\u4e86 3 \u53f7\u67dc，\u518d\u770b\u91cc\u9762\u662f\u4e0d\u662f\u4f60\u7684\u5305\u88f9\u3002<\/p>\n

hashCode() \u5c31\u50cf\u201c\u5148\u544a\u8bc9\u4f60\u53bb\u54ea\u4e2a\u67dc\u5b50\u627e\u201d\u3002
\nequals() \u5c31\u50cf\u201c\u5230\u67dc\u5b50\u91cc\u4ee5\u540e\u786e\u8ba4\u662f\u4e0d\u662f\u4f60\u7684\u5305\u88f9\u201d\u3002<\/p>\n

#mermaid-svg-3BjnCB4GE2Kykwab{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;fill:#333;}@keyframes edge-animation-frame{from{stroke-dashoffset:0;}}@keyframes dash{to{stroke-dashoffset:0;}}#mermaid-svg-3BjnCB4GE2Kykwab .edge-animation-slow{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 50s linear infinite;stroke-linecap:round;}#mermaid-svg-3BjnCB4GE2Kykwab .edge-animation-fast{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 20s linear infinite;stroke-linecap:round;}#mermaid-svg-3BjnCB4GE2Kykwab .error-icon{fill:#552222;}#mermaid-svg-3BjnCB4GE2Kykwab .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-3BjnCB4GE2Kykwab .edge-thickness-normal{stroke-width:1px;}#mermaid-svg-3BjnCB4GE2Kykwab .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-3BjnCB4GE2Kykwab .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-3BjnCB4GE2Kykwab .edge-thickness-invisible{stroke-width:0;fill:none;}#mermaid-svg-3BjnCB4GE2Kykwab .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-3BjnCB4GE2Kykwab .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-3BjnCB4GE2Kykwab .marker{fill:#333333;stroke:#333333;}#mermaid-svg-3BjnCB4GE2Kykwab .marker.cross{stroke:#333333;}#mermaid-svg-3BjnCB4GE2Kykwab svg{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-3BjnCB4GE2Kykwab p{margin:0;}#mermaid-svg-3BjnCB4GE2Kykwab .label{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;color:#333;}#mermaid-svg-3BjnCB4GE2Kykwab .cluster-label text{fill:#333;}#mermaid-svg-3BjnCB4GE2Kykwab .cluster-label span{color:#333;}#mermaid-svg-3BjnCB4GE2Kykwab .cluster-label span p{background-color:transparent;}#mermaid-svg-3BjnCB4GE2Kykwab .label text,#mermaid-svg-3BjnCB4GE2Kykwab span{fill:#333;color:#333;}#mermaid-svg-3BjnCB4GE2Kykwab .node rect,#mermaid-svg-3BjnCB4GE2Kykwab .node circle,#mermaid-svg-3BjnCB4GE2Kykwab .node ellipse,#mermaid-svg-3BjnCB4GE2Kykwab .node polygon,#mermaid-svg-3BjnCB4GE2Kykwab .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-3BjnCB4GE2Kykwab .rough-node .label text,#mermaid-svg-3BjnCB4GE2Kykwab .node .label text,#mermaid-svg-3BjnCB4GE2Kykwab .image-shape .label,#mermaid-svg-3BjnCB4GE2Kykwab .icon-shape .label{text-anchor:middle;}#mermaid-svg-3BjnCB4GE2Kykwab .node .katex path{fill:#000;stroke:#000;stroke-width:1px;}#mermaid-svg-3BjnCB4GE2Kykwab .rough-node .label,#mermaid-svg-3BjnCB4GE2Kykwab .node .label,#mermaid-svg-3BjnCB4GE2Kykwab .image-shape .label,#mermaid-svg-3BjnCB4GE2Kykwab .icon-shape .label{text-align:center;}#mermaid-svg-3BjnCB4GE2Kykwab .node.clickable{cursor:pointer;}#mermaid-svg-3BjnCB4GE2Kykwab .root .anchor path{fill:#333333!important;stroke-width:0;stroke:#333333;}#mermaid-svg-3BjnCB4GE2Kykwab .arrowheadPath{fill:#333333;}#mermaid-svg-3BjnCB4GE2Kykwab .edgePath .path{stroke:#333333;stroke-width:2.0px;}#mermaid-svg-3BjnCB4GE2Kykwab .flowchart-link{stroke:#333333;fill:none;}#mermaid-svg-3BjnCB4GE2Kykwab .edgeLabel{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-3BjnCB4GE2Kykwab .edgeLabel p{background-color:rgba(232,232,232, 0.8);}#mermaid-svg-3BjnCB4GE2Kykwab .edgeLabel rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-3BjnCB4GE2Kykwab .labelBkg{background-color:rgba(232, 232, 232, 0.5);}#mermaid-svg-3BjnCB4GE2Kykwab .cluster rect{fill:#ffffde;stroke:#aaaa33;stroke-width:1px;}#mermaid-svg-3BjnCB4GE2Kykwab .cluster text{fill:#333;}#mermaid-svg-3BjnCB4GE2Kykwab .cluster span{color:#333;}#mermaid-svg-3BjnCB4GE2Kykwab div.mermaidTooltip{position:absolute;text-align:center;max-width:200px;padding:2px;font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:12px;background:hsl(80, 100%, 96.2745098039%);border:1px solid #aaaa33;border-radius:2px;pointer-events:none;z-index:100;}#mermaid-svg-3BjnCB4GE2Kykwab .flowchartTitleText{text-anchor:middle;font-size:18px;fill:#333;}#mermaid-svg-3BjnCB4GE2Kykwab rect.text{fill:none;stroke-width:0;}#mermaid-svg-3BjnCB4GE2Kykwab .icon-shape,#mermaid-svg-3BjnCB4GE2Kykwab .image-shape{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-3BjnCB4GE2Kykwab .icon-shape p,#mermaid-svg-3BjnCB4GE2Kykwab .image-shape p{background-color:rgba(232,232,232, 0.8);padding:2px;}#mermaid-svg-3BjnCB4GE2Kykwab .icon-shape .label rect,#mermaid-svg-3BjnCB4GE2Kykwab .image-shape .label rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-3BjnCB4GE2Kykwab .label-icon{display:inline-block;height:1em;overflow:visible;vertical-align:-0.125em;}#mermaid-svg-3BjnCB4GE2Kykwab .node .label-icon path{fill:currentColor;stroke:revert;stroke-width:revert;}#mermaid-svg-3BjnCB4GE2Kykwab :root{–mermaid-font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;}<\/span><\/span><\/span><\/span><\/p>\n

\u662f<\/p>\n

<\/span><\/p>\n

\u5426<\/p>\n

<\/span><\/p>\n

\u4e00\u4e2a\u5bf9\u8c61\u8981\u653e\u8fdb HashMap \u6216 HashSet<\/p>\n

<\/span><\/p>\n

\u5148\u7b97 hashCode<\/p>\n

<\/span><\/p>\n

\u6839\u636e hash \u627e\u5230\u6876<\/p>\n

<\/span><\/p>\n

\u6876\u91cc\u53ef\u80fd\u6709\u591a\u4e2a\u5bf9\u8c61，\u518d\u7528 equals \u786e\u8ba4<\/p>\n

<\/span><\/p>\n

\u662f\u4e0d\u662f\u540c\u4e00\u4e2a key<\/p>\n

<\/span><\/p>\n

\u8986\u76d6\u6216\u53bb\u91cd<\/p>\n

<\/span><\/p>\n

\u540c\u6876\u4f46\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61<\/p>\n

<\/span><\/p>\n

\u6240\u4ee5\u89c4\u5219\u662f：<\/p>\n

\u5982\u679c\u4e24\u4e2a\u5bf9\u8c61 equals \u662f true，
\n\u90a3\u4e48\u5b83\u4eec\u7684 hashCode \u5fc5\u987b\u4e00\u6837\u3002<\/p>\n

\u53cd\u8fc7\u6765\u4e0d\u4e00\u5b9a：<\/p>\n

\u4e24\u4e2a\u5bf9\u8c61 hashCode \u4e00\u6837，
\nequals \u4e0d\u4e00\u5b9a\u662f true\u3002<\/p>\n

\u56e0\u4e3a\u4e0d\u540c\u5305\u88f9\u53ef\u80fd\u521a\u597d\u88ab\u5206\u5230\u4e86\u540c\u4e00\u4e2a\u67dc\u5b50，\u8fd9\u53eb hash \u51b2\u7a81\u3002<\/p>\n

8. \u53ea\u5199 equals() \u4e0d\u5199 hashCode() \u4f1a\u53d1\u751f\u4ec0\u4e48<\/h3>\n

\u770b\u8fd9\u4e2a\u9519\u8bef\u5199\u6cd5：<\/p>\n

public<\/span> final<\/span> class<\/span> User<\/span> {<\/span>
\n private<\/span> final<\/span> long<\/span> id;<\/span><\/p>\n

public<\/span> User<\/span>(<\/span>long<\/span> id)<\/span> {<\/span>
\n this<\/span>.<\/span>id =<\/span> id;<\/span>
\n }<\/span><\/p>\n

@Override<\/span>
\n public<\/span> boolean<\/span> equals<\/span>(<\/span>Object<\/span> obj)<\/span> {<\/span>
\n if<\/span> (<\/span>this<\/span> ==<\/span> obj)<\/span> return<\/span> true<\/span>;<\/span>
\n if<\/span> (<\/span>!<\/span>(<\/span>obj instanceof<\/span> User<\/span>)<\/span>)<\/span> return<\/span> false<\/span>;<\/span>
\n return<\/span> this<\/span>.<\/span>id ==<\/span> (<\/span>(<\/span>User<\/span>)<\/span> obj)<\/span>.<\/span>id;<\/span>
\n }<\/span>
\n}<\/span><\/p>\n

\u4f60\u89c9\u5f97\u4e0b\u9762\u96c6\u5408\u91cc\u6709\u51e0\u4e2a\u5143\u7d20？<\/p>\n

Set<\/span><<\/span>User<\/span>><\/span><\/span> users =<\/span> new<\/span> HashSet<\/span><<\/span>><\/span><\/span>(<\/span>)<\/span>;<\/span>
\nusers.<\/span>add<\/span>(<\/span>new<\/span> User<\/span>(<\/span>1<\/span>)<\/span>)<\/span>;<\/span>
\nusers.<\/span>add<\/span>(<\/span>new<\/span> User<\/span>(<\/span>1<\/span>)<\/span>)<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>users.<\/span>size<\/span>(<\/span>)<\/span>)<\/span>;<\/span><\/p>\n

\u4f60\u4e1a\u52a1\u4e0a\u4f1a\u89c9\u5f97\u5e94\u8be5\u662f 1\u3002\u56e0\u4e3a\u4e24\u4e2a\u7528\u6237 id \u90fd\u662f 1\u3002<\/p>\n

\u4f46\u5b9e\u9645\u53ef\u80fd\u662f 2\u3002<\/p>\n

\u4e3a\u4ec0\u4e48？<\/p>\n

\u56e0\u4e3a\u4f60\u53ea\u544a\u8bc9 Java：\u201c\u4e24\u4e2a id \u4e00\u6837\u7684 User \u7b97\u76f8\u7b49\u3002\u201d
\n\u4f46\u4f60\u6ca1\u6709\u544a\u8bc9\u54c8\u5e0c\u96c6\u5408：\u201c\u5b83\u4eec\u5e94\u8be5\u53bb\u540c\u4e00\u4e2a\u6876\u91cc\u627e\u3002\u201d<\/p>\n

#mermaid-svg-QV9blz8RuW9cvd2C{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;fill:#333;}@keyframes edge-animation-frame{from{stroke-dashoffset:0;}}@keyframes dash{to{stroke-dashoffset:0;}}#mermaid-svg-QV9blz8RuW9cvd2C .edge-animation-slow{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 50s linear infinite;stroke-linecap:round;}#mermaid-svg-QV9blz8RuW9cvd2C .edge-animation-fast{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 20s linear infinite;stroke-linecap:round;}#mermaid-svg-QV9blz8RuW9cvd2C .error-icon{fill:#552222;}#mermaid-svg-QV9blz8RuW9cvd2C .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-QV9blz8RuW9cvd2C .edge-thickness-normal{stroke-width:1px;}#mermaid-svg-QV9blz8RuW9cvd2C .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-QV9blz8RuW9cvd2C .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-QV9blz8RuW9cvd2C .edge-thickness-invisible{stroke-width:0;fill:none;}#mermaid-svg-QV9blz8RuW9cvd2C .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-QV9blz8RuW9cvd2C .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-QV9blz8RuW9cvd2C .marker{fill:#333333;stroke:#333333;}#mermaid-svg-QV9blz8RuW9cvd2C .marker.cross{stroke:#333333;}#mermaid-svg-QV9blz8RuW9cvd2C svg{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-QV9blz8RuW9cvd2C p{margin:0;}#mermaid-svg-QV9blz8RuW9cvd2C .label{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;color:#333;}#mermaid-svg-QV9blz8RuW9cvd2C .cluster-label text{fill:#333;}#mermaid-svg-QV9blz8RuW9cvd2C .cluster-label span{color:#333;}#mermaid-svg-QV9blz8RuW9cvd2C .cluster-label span p{background-color:transparent;}#mermaid-svg-QV9blz8RuW9cvd2C .label text,#mermaid-svg-QV9blz8RuW9cvd2C span{fill:#333;color:#333;}#mermaid-svg-QV9blz8RuW9cvd2C .node rect,#mermaid-svg-QV9blz8RuW9cvd2C .node circle,#mermaid-svg-QV9blz8RuW9cvd2C .node ellipse,#mermaid-svg-QV9blz8RuW9cvd2C .node polygon,#mermaid-svg-QV9blz8RuW9cvd2C .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-QV9blz8RuW9cvd2C .rough-node .label text,#mermaid-svg-QV9blz8RuW9cvd2C .node .label text,#mermaid-svg-QV9blz8RuW9cvd2C .image-shape .label,#mermaid-svg-QV9blz8RuW9cvd2C .icon-shape .label{text-anchor:middle;}#mermaid-svg-QV9blz8RuW9cvd2C .node .katex path{fill:#000;stroke:#000;stroke-width:1px;}#mermaid-svg-QV9blz8RuW9cvd2C .rough-node .label,#mermaid-svg-QV9blz8RuW9cvd2C .node .label,#mermaid-svg-QV9blz8RuW9cvd2C .image-shape .label,#mermaid-svg-QV9blz8RuW9cvd2C .icon-shape .label{text-align:center;}#mermaid-svg-QV9blz8RuW9cvd2C .node.clickable{cursor:pointer;}#mermaid-svg-QV9blz8RuW9cvd2C .root .anchor path{fill:#333333!important;stroke-width:0;stroke:#333333;}#mermaid-svg-QV9blz8RuW9cvd2C .arrowheadPath{fill:#333333;}#mermaid-svg-QV9blz8RuW9cvd2C .edgePath .path{stroke:#333333;stroke-width:2.0px;}#mermaid-svg-QV9blz8RuW9cvd2C .flowchart-link{stroke:#333333;fill:none;}#mermaid-svg-QV9blz8RuW9cvd2C .edgeLabel{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-QV9blz8RuW9cvd2C .edgeLabel p{background-color:rgba(232,232,232, 0.8);}#mermaid-svg-QV9blz8RuW9cvd2C .edgeLabel rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-QV9blz8RuW9cvd2C .labelBkg{background-color:rgba(232, 232, 232, 0.5);}#mermaid-svg-QV9blz8RuW9cvd2C .cluster rect{fill:#ffffde;stroke:#aaaa33;stroke-width:1px;}#mermaid-svg-QV9blz8RuW9cvd2C .cluster text{fill:#333;}#mermaid-svg-QV9blz8RuW9cvd2C .cluster span{color:#333;}#mermaid-svg-QV9blz8RuW9cvd2C div.mermaidTooltip{position:absolute;text-align:center;max-width:200px;padding:2px;font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:12px;background:hsl(80, 100%, 96.2745098039%);border:1px solid #aaaa33;border-radius:2px;pointer-events:none;z-index:100;}#mermaid-svg-QV9blz8RuW9cvd2C .flowchartTitleText{text-anchor:middle;font-size:18px;fill:#333;}#mermaid-svg-QV9blz8RuW9cvd2C rect.text{fill:none;stroke-width:0;}#mermaid-svg-QV9blz8RuW9cvd2C .icon-shape,#mermaid-svg-QV9blz8RuW9cvd2C .image-shape{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-QV9blz8RuW9cvd2C .icon-shape p,#mermaid-svg-QV9blz8RuW9cvd2C .image-shape p{background-color:rgba(232,232,232, 0.8);padding:2px;}#mermaid-svg-QV9blz8RuW9cvd2C .icon-shape .label rect,#mermaid-svg-QV9blz8RuW9cvd2C .image-shape .label rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-QV9blz8RuW9cvd2C .label-icon{display:inline-block;height:1em;overflow:visible;vertical-align:-0.125em;}#mermaid-svg-QV9blz8RuW9cvd2C .node .label-icon path{fill:currentColor;stroke:revert;stroke-width:revert;}#mermaid-svg-QV9blz8RuW9cvd2C :root{–mermaid-font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;}<\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/p>\n

new User \u4e00：id \u4e3a 1<\/p>\n

<\/span><\/p>\n

new User \u4e8c：id \u4e3a 1<\/p>\n

<\/span><\/p>\n

\u9ed8\u8ba4 hashCode \u4e00<\/p>\n

<\/span><\/p>\n

\u9ed8\u8ba4 hashCode \u4e8c<\/p>\n

<\/span><\/p>\n

\u8fdb\u5165\u6876\u4e00<\/p>\n

<\/span><\/p>\n

\u8fdb\u5165\u6876\u4e8c<\/p>\n

<\/span><\/p>\n

HashSet \u6ca1\u6709\u673a\u4f1a\u6bd4\u8f83 equals<\/p>\n

<\/span><\/p>\n

\u6700\u540e\u7559\u4e0b\u4e24\u4e2a\u770b\u8d77\u6765\u76f8\u540c\u7684\u7528\u6237<\/p>\n

<\/span><\/p>\n

\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u5e38\u8bf4：<\/p>\n

\u53ea\u8981\u91cd\u5199 equals()，\u901a\u5e38\u5c31\u5fc5\u987b\u91cd\u5199 hashCode()\u3002<\/p>\n

\u4e0d\u7136 HashMap\u3001HashSet \u8fd9\u7c7b\u96c6\u5408\u5c31\u53ef\u80fd\u8868\u73b0\u5f97\u5f88\u5947\u602a\u3002<\/p>\n

9. HashMap \u67e5 key，\u5176\u5b9e\u5c31\u662f\u4e24\u6b65<\/h3>\n

HashMap \u627e\u4e00\u4e2a key，\u53ef\u4ee5\u7406\u89e3\u6210：<\/p>\n

\u7b2c\u4e00\u6b65：\u5148\u6839\u636e hashCode \u627e\u67dc\u5b50\u3002
\n\u7b2c\u4e8c\u6b65：\u67dc\u5b50\u91cc\u518d\u7528 equals \u786e\u8ba4\u662f\u4e0d\u662f\u5b83\u3002<\/p>\n

\u7b80\u5316\u4f2a\u4ee3\u7801：<\/p>\n

\/\/ \u7b80\u5316\u7406\u89e3，\u4e0d\u662f\u9010\u884c\u6e90\u7801<\/span>
\nV<\/span> get<\/span>(<\/span>Object<\/span> key)<\/span> {<\/span>
\n int<\/span> hash =<\/span> key.<\/span>hashCode<\/span>(<\/span>)<\/span>;<\/span>
\n Bucket<\/span> bucket =<\/span> findBucket<\/span>(<\/span>hash)<\/span>;<\/span><\/p>\n

for<\/span> (<\/span>Node<\/span> node :<\/span> bucket)<\/span> {<\/span>
\n if<\/span> (<\/span>node.<\/span>hash ==<\/span> hash &&<\/span>
\n (<\/span>node.<\/span>key ==<\/span> key ||<\/span> key.<\/span>equals<\/span>(<\/span>node.<\/span>key)<\/span>)<\/span>)<\/span> {<\/span>
\n return<\/span> node.<\/span>value;<\/span>
\n }<\/span>
\n }<\/span>
\n return<\/span> null<\/span>;<\/span>
\n}<\/span><\/p>\n

\u6ce8\u610f\u8fd9\u53e5：<\/p>\n

node.<\/span>key ==<\/span> key ||<\/span> key.<\/span>equals<\/span>(<\/span>node.<\/span>key)<\/span><\/p>\n

\u610f\u601d\u662f：<\/p>\n

\u5982\u679c\u672c\u6765\u5c31\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61，\u90a3\u80af\u5b9a\u662f\u540c\u4e00\u4e2a key\u3002
\n\u5982\u679c\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61，\u518d\u770b\u770b equals \u8ba4\u4e3a\u5b83\u4eec\u662f\u4e0d\u662f\u540c\u4e00\u4e2a key\u3002<\/p>\n

\u8fd9\u4e5f\u662f\u9762\u8bd5\u5b98\u559c\u6b22\u4ece equals() \u8ffd\u5230 HashMap \u7684\u539f\u56e0\u3002\u5b83\u4e0d\u662f\u7a81\u7136\u6362\u9898，\u800c\u662f\u987a\u7740\u540c\u4e00\u6761\u7ebf\u5f80\u4e0b\u95ee\u3002<\/p>\n

10. \u53ef\u53d8\u5bf9\u8c61\u5f53 key，\u5f88\u5bb9\u6613\u628a\u81ea\u5df1\u5751\u4f4f<\/h3>\n

\u518d\u770b\u4e00\u4e2a\u771f\u5b9e\u5de5\u4f5c\u91cc\u4f1a\u8e29\u7684\u5751\u3002<\/p>\n

User<\/span> user =<\/span> new<\/span> User<\/span>(<\/span>1<\/span>)<\/span>;<\/span>
\nMap<\/span><<\/span>User<\/span>,<\/span> String<\/span>><\/span><\/span> map =<\/span> new<\/span> HashMap<\/span><<\/span>><\/span><\/span>(<\/span>)<\/span>;<\/span>
\nmap.<\/span>put<\/span>(<\/span>user,<\/span> "\u5f20\u4e09"<\/span>)<\/span>;<\/span><\/p>\n

user.<\/span>setId<\/span>(<\/span>2<\/span>)<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>map.<\/span>get<\/span>(<\/span>user)<\/span>)<\/span>;<\/span> \/\/ \u53ef\u80fd\u62ff\u4e0d\u5230<\/span><\/p>\n

\u4e3a\u4ec0\u4e48？<\/p>\n

\u4f60\u53ef\u4ee5\u60f3\u6210：<\/p>\n

\u653e\u8fdb\u53bb\u7684\u65f6\u5019，id \u662f 1，\u6240\u4ee5\u653e\u8fdb\u4e86 1 \u53f7\u67dc\u3002
\n\u540e\u6765\u4f60\u628a id \u6539\u6210 2\u3002
\n\u518d\u53bb\u53d6\u7684\u65f6\u5019，\u7cfb\u7edf\u8ba9\u4f60\u53bb 2 \u53f7\u67dc\u627e\u3002
\n\u53ef\u4e1c\u897f\u8fd8\u5728 1 \u53f7\u67dc\u91cc\u3002
\n\u6240\u4ee5\u627e\u4e0d\u5230\u3002<\/p>\n

#mermaid-svg-w0dsLk1KNTnNfV1y{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;fill:#333;}@keyframes edge-animation-frame{from{stroke-dashoffset:0;}}@keyframes dash{to{stroke-dashoffset:0;}}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-animation-slow{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 50s linear infinite;stroke-linecap:round;}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-animation-fast{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 20s linear infinite;stroke-linecap:round;}#mermaid-svg-w0dsLk1KNTnNfV1y .error-icon{fill:#552222;}#mermaid-svg-w0dsLk1KNTnNfV1y .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-thickness-normal{stroke-width:1px;}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-thickness-invisible{stroke-width:0;fill:none;}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-w0dsLk1KNTnNfV1y .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-w0dsLk1KNTnNfV1y .marker{fill:#333333;stroke:#333333;}#mermaid-svg-w0dsLk1KNTnNfV1y .marker.cross{stroke:#333333;}#mermaid-svg-w0dsLk1KNTnNfV1y svg{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-w0dsLk1KNTnNfV1y p{margin:0;}#mermaid-svg-w0dsLk1KNTnNfV1y .label{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;color:#333;}#mermaid-svg-w0dsLk1KNTnNfV1y .cluster-label text{fill:#333;}#mermaid-svg-w0dsLk1KNTnNfV1y .cluster-label span{color:#333;}#mermaid-svg-w0dsLk1KNTnNfV1y .cluster-label span p{background-color:transparent;}#mermaid-svg-w0dsLk1KNTnNfV1y .label text,#mermaid-svg-w0dsLk1KNTnNfV1y span{fill:#333;color:#333;}#mermaid-svg-w0dsLk1KNTnNfV1y .node rect,#mermaid-svg-w0dsLk1KNTnNfV1y .node circle,#mermaid-svg-w0dsLk1KNTnNfV1y .node ellipse,#mermaid-svg-w0dsLk1KNTnNfV1y .node polygon,#mermaid-svg-w0dsLk1KNTnNfV1y .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-w0dsLk1KNTnNfV1y .rough-node .label text,#mermaid-svg-w0dsLk1KNTnNfV1y .node .label text,#mermaid-svg-w0dsLk1KNTnNfV1y .image-shape .label,#mermaid-svg-w0dsLk1KNTnNfV1y .icon-shape .label{text-anchor:middle;}#mermaid-svg-w0dsLk1KNTnNfV1y .node .katex path{fill:#000;stroke:#000;stroke-width:1px;}#mermaid-svg-w0dsLk1KNTnNfV1y .rough-node .label,#mermaid-svg-w0dsLk1KNTnNfV1y .node .label,#mermaid-svg-w0dsLk1KNTnNfV1y .image-shape .label,#mermaid-svg-w0dsLk1KNTnNfV1y .icon-shape .label{text-align:center;}#mermaid-svg-w0dsLk1KNTnNfV1y .node.clickable{cursor:pointer;}#mermaid-svg-w0dsLk1KNTnNfV1y .root .anchor path{fill:#333333!important;stroke-width:0;stroke:#333333;}#mermaid-svg-w0dsLk1KNTnNfV1y .arrowheadPath{fill:#333333;}#mermaid-svg-w0dsLk1KNTnNfV1y .edgePath .path{stroke:#333333;stroke-width:2.0px;}#mermaid-svg-w0dsLk1KNTnNfV1y .flowchart-link{stroke:#333333;fill:none;}#mermaid-svg-w0dsLk1KNTnNfV1y .edgeLabel{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-w0dsLk1KNTnNfV1y .edgeLabel p{background-color:rgba(232,232,232, 0.8);}#mermaid-svg-w0dsLk1KNTnNfV1y .edgeLabel rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-w0dsLk1KNTnNfV1y .labelBkg{background-color:rgba(232, 232, 232, 0.5);}#mermaid-svg-w0dsLk1KNTnNfV1y .cluster rect{fill:#ffffde;stroke:#aaaa33;stroke-width:1px;}#mermaid-svg-w0dsLk1KNTnNfV1y .cluster text{fill:#333;}#mermaid-svg-w0dsLk1KNTnNfV1y .cluster span{color:#333;}#mermaid-svg-w0dsLk1KNTnNfV1y div.mermaidTooltip{position:absolute;text-align:center;max-width:200px;padding:2px;font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:12px;background:hsl(80, 100%, 96.2745098039%);border:1px solid #aaaa33;border-radius:2px;pointer-events:none;z-index:100;}#mermaid-svg-w0dsLk1KNTnNfV1y .flowchartTitleText{text-anchor:middle;font-size:18px;fill:#333;}#mermaid-svg-w0dsLk1KNTnNfV1y rect.text{fill:none;stroke-width:0;}#mermaid-svg-w0dsLk1KNTnNfV1y .icon-shape,#mermaid-svg-w0dsLk1KNTnNfV1y .image-shape{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-w0dsLk1KNTnNfV1y .icon-shape p,#mermaid-svg-w0dsLk1KNTnNfV1y .image-shape p{background-color:rgba(232,232,232, 0.8);padding:2px;}#mermaid-svg-w0dsLk1KNTnNfV1y .icon-shape .label rect,#mermaid-svg-w0dsLk1KNTnNfV1y .image-shape .label rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-w0dsLk1KNTnNfV1y .label-icon{display:inline-block;height:1em;overflow:visible;vertical-align:-0.125em;}#mermaid-svg-w0dsLk1KNTnNfV1y .node .label-icon path{fill:currentColor;stroke:revert;stroke-width:revert;}#mermaid-svg-w0dsLk1KNTnNfV1y :root{–mermaid-font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;}<\/span><\/span><\/span><\/span><\/p>\n

put \u65f6 id \u662f 1<\/p>\n

<\/span><\/p>\n

\u6309 id \u4e3a 1 \u653e\u8fdb\u6876\u4e00<\/p>\n

<\/span><\/p>\n

\u4e2d\u9014\u628a id \u6539\u6210 2<\/p>\n

<\/span><\/p>\n

get \u65f6\u53bb\u6876\u4e8c\u627e<\/p>\n

<\/span><\/p>\n

\u6876\u4e8c\u6ca1\u6709\u8fd9\u4e2a\u5bf9\u8c61<\/p>\n

<\/span><\/p>\n

\u5bf9\u8c61\u5176\u5b9e\u8fd8\u5728\u6876\u4e00<\/p>\n

<\/span><\/p>\n

\u6240\u4ee5\u7ecf\u9a8c\u662f：<\/p>\n

\u5982\u679c\u4e00\u4e2a\u5bf9\u8c61\u8981\u5f53 HashMap \u7684 key，\u53c2\u4e0e equals() \u548c hashCode() \u7684\u5b57\u6bb5\u5c3d\u91cf\u4e0d\u8981\u53d8\u3002<\/p>\n

11. Objects.equals() \u53ea\u662f\u5e2e\u4f60\u5c11\u5199\u7a7a\u5224\u65ad<\/h3>\n

\u6709\u65f6\u4f60\u4f1a\u770b\u5230\u8fd9\u79cd\u5199\u6cd5：<\/p>\n

Objects<\/span>.<\/span>equals<\/span>(<\/span>a,<\/span> b)<\/span><\/p>\n

\u5b83\u5927\u6982\u7b49\u4e8e：<\/p>\n

a ==<\/span> b ||<\/span> (<\/span>a !=<\/span> null<\/span> &&<\/span> a.<\/span>equals<\/span>(<\/span>b)<\/span>)<\/span><\/p>\n

\u5b83\u7684\u597d\u5904\u662f：\u4e0d\u6015 a \u662f null\u3002<\/p>\n

\u4f46\u5b83\u4e0d\u662f\u9b54\u6cd5\u3002\u5b83\u4e0d\u4f1a\u5e2e\u4f60\u51b3\u5b9a\u4ec0\u4e48\u53eb\u201c\u4e1a\u52a1\u4e0a\u76f8\u7b49\u201d\u3002\u6700\u7ec8\u8fd8\u662f\u8981\u770b a.equals(b) \u81ea\u5df1\u600e\u4e48\u5199\u3002<\/p>\n

12. Android \u91cc\u8fd9\u4e2a\u95ee\u9898\u7279\u522b\u5e38\u89c1<\/h3>\n

\u8fd9\u9898\u4e0d\u662f\u53ea\u5728 Java \u9762\u8bd5\u91cc\u51fa\u73b0\u3002Android \u91cc\u4e5f\u7ecf\u5e38\u9047\u5230\u3002<\/p>\n

RecyclerView \u5217\u8868\u5237\u65b0<\/h4>\n

DiffUtil \u4f1a\u95ee\u4e24\u4e2a\u95ee\u9898：<\/p>\n

public<\/span> class<\/span> UserDiff<\/span> extends<\/span> DiffUtil.<\/span>ItemCallback<\/span><<\/span>User<\/span>><\/span><\/span> {<\/span>
\n @Override<\/span>
\n public<\/span> boolean<\/span> areItemsTheSame<\/span>(<\/span>User<\/span> oldItem,<\/span> User<\/span> newItem)<\/span> {<\/span>
\n return<\/span> oldItem.<\/span>getId<\/span>(<\/span>)<\/span> ==<\/span> newItem.<\/span>getId<\/span>(<\/span>)<\/span>;<\/span>
\n }<\/span><\/p>\n

@Override<\/span>
\n public<\/span> boolean<\/span> areContentsTheSame<\/span>(<\/span>User<\/span> oldItem,<\/span> User<\/span> newItem)<\/span> {<\/span>
\n return<\/span> oldItem.<\/span>equals<\/span>(<\/span>newItem)<\/span>;<\/span>
\n }<\/span>
\n}<\/span><\/p>\n

\u8fd9\u4e24\u4e2a\u65b9\u6cd5\u5176\u5b9e\u5f88\u50cf\u4eca\u5929\u8bb2\u7684\u5185\u5bb9\u3002<\/p>\n

areItemsTheSame：
\n \u8fd9\u662f\u4e0d\u662f\u540c\u4e00\u6761\u6570\u636e？
\n \u5e38\u89c1\u5c31\u662f\u6bd4\u8f83 id\u3002<\/p>\n

areContentsTheSame：
\n \u8fd9\u6761\u6570\u636e\u7684\u5c55\u793a\u5185\u5bb9\u6709\u6ca1\u6709\u53d8？
\n \u53ef\u4ee5\u6bd4\u8f83\u6574\u4e2a\u5bf9\u8c61\u5185\u5bb9\u3002<\/p>\n

#mermaid-svg-41Unc4IlauqK8zYP{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;fill:#333;}@keyframes edge-animation-frame{from{stroke-dashoffset:0;}}@keyframes dash{to{stroke-dashoffset:0;}}#mermaid-svg-41Unc4IlauqK8zYP .edge-animation-slow{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 50s linear infinite;stroke-linecap:round;}#mermaid-svg-41Unc4IlauqK8zYP .edge-animation-fast{stroke-dasharray:9,5!important;stroke-dashoffset:900;animation:dash 20s linear infinite;stroke-linecap:round;}#mermaid-svg-41Unc4IlauqK8zYP .error-icon{fill:#552222;}#mermaid-svg-41Unc4IlauqK8zYP .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-41Unc4IlauqK8zYP .edge-thickness-normal{stroke-width:1px;}#mermaid-svg-41Unc4IlauqK8zYP .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-41Unc4IlauqK8zYP .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-41Unc4IlauqK8zYP .edge-thickness-invisible{stroke-width:0;fill:none;}#mermaid-svg-41Unc4IlauqK8zYP .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-41Unc4IlauqK8zYP .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-41Unc4IlauqK8zYP .marker{fill:#333333;stroke:#333333;}#mermaid-svg-41Unc4IlauqK8zYP .marker.cross{stroke:#333333;}#mermaid-svg-41Unc4IlauqK8zYP svg{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-41Unc4IlauqK8zYP p{margin:0;}#mermaid-svg-41Unc4IlauqK8zYP .label{font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;color:#333;}#mermaid-svg-41Unc4IlauqK8zYP .cluster-label text{fill:#333;}#mermaid-svg-41Unc4IlauqK8zYP .cluster-label span{color:#333;}#mermaid-svg-41Unc4IlauqK8zYP .cluster-label span p{background-color:transparent;}#mermaid-svg-41Unc4IlauqK8zYP .label text,#mermaid-svg-41Unc4IlauqK8zYP span{fill:#333;color:#333;}#mermaid-svg-41Unc4IlauqK8zYP .node rect,#mermaid-svg-41Unc4IlauqK8zYP .node circle,#mermaid-svg-41Unc4IlauqK8zYP .node ellipse,#mermaid-svg-41Unc4IlauqK8zYP .node polygon,#mermaid-svg-41Unc4IlauqK8zYP .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-41Unc4IlauqK8zYP .rough-node .label text,#mermaid-svg-41Unc4IlauqK8zYP .node .label text,#mermaid-svg-41Unc4IlauqK8zYP .image-shape .label,#mermaid-svg-41Unc4IlauqK8zYP .icon-shape .label{text-anchor:middle;}#mermaid-svg-41Unc4IlauqK8zYP .node .katex path{fill:#000;stroke:#000;stroke-width:1px;}#mermaid-svg-41Unc4IlauqK8zYP .rough-node .label,#mermaid-svg-41Unc4IlauqK8zYP .node .label,#mermaid-svg-41Unc4IlauqK8zYP .image-shape .label,#mermaid-svg-41Unc4IlauqK8zYP .icon-shape .label{text-align:center;}#mermaid-svg-41Unc4IlauqK8zYP .node.clickable{cursor:pointer;}#mermaid-svg-41Unc4IlauqK8zYP .root .anchor path{fill:#333333!important;stroke-width:0;stroke:#333333;}#mermaid-svg-41Unc4IlauqK8zYP .arrowheadPath{fill:#333333;}#mermaid-svg-41Unc4IlauqK8zYP .edgePath .path{stroke:#333333;stroke-width:2.0px;}#mermaid-svg-41Unc4IlauqK8zYP .flowchart-link{stroke:#333333;fill:none;}#mermaid-svg-41Unc4IlauqK8zYP .edgeLabel{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-41Unc4IlauqK8zYP .edgeLabel p{background-color:rgba(232,232,232, 0.8);}#mermaid-svg-41Unc4IlauqK8zYP .edgeLabel rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-41Unc4IlauqK8zYP .labelBkg{background-color:rgba(232, 232, 232, 0.5);}#mermaid-svg-41Unc4IlauqK8zYP .cluster rect{fill:#ffffde;stroke:#aaaa33;stroke-width:1px;}#mermaid-svg-41Unc4IlauqK8zYP .cluster text{fill:#333;}#mermaid-svg-41Unc4IlauqK8zYP .cluster span{color:#333;}#mermaid-svg-41Unc4IlauqK8zYP div.mermaidTooltip{position:absolute;text-align:center;max-width:200px;padding:2px;font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;font-size:12px;background:hsl(80, 100%, 96.2745098039%);border:1px solid #aaaa33;border-radius:2px;pointer-events:none;z-index:100;}#mermaid-svg-41Unc4IlauqK8zYP .flowchartTitleText{text-anchor:middle;font-size:18px;fill:#333;}#mermaid-svg-41Unc4IlauqK8zYP rect.text{fill:none;stroke-width:0;}#mermaid-svg-41Unc4IlauqK8zYP .icon-shape,#mermaid-svg-41Unc4IlauqK8zYP .image-shape{background-color:rgba(232,232,232, 0.8);text-align:center;}#mermaid-svg-41Unc4IlauqK8zYP .icon-shape p,#mermaid-svg-41Unc4IlauqK8zYP .image-shape p{background-color:rgba(232,232,232, 0.8);padding:2px;}#mermaid-svg-41Unc4IlauqK8zYP .icon-shape .label rect,#mermaid-svg-41Unc4IlauqK8zYP .image-shape .label rect{opacity:0.5;background-color:rgba(232,232,232, 0.8);fill:rgba(232,232,232, 0.8);}#mermaid-svg-41Unc4IlauqK8zYP .label-icon{display:inline-block;height:1em;overflow:visible;vertical-align:-0.125em;}#mermaid-svg-41Unc4IlauqK8zYP .node .label-icon path{fill:currentColor;stroke:revert;stroke-width:revert;}#mermaid-svg-41Unc4IlauqK8zYP :root{–mermaid-font-family:\\”trebuchet ms\\”,verdana,arial,sans-serif;}<\/span><\/span><\/p>\n

\u5426<\/p>\n

<\/span><\/p>\n

\u662f<\/p>\n

<\/span><\/p>\n

\u662f<\/p>\n

<\/span><\/p>\n

\u5426<\/p>\n

<\/span><\/p>\n

\u65e7\u5217\u8868\u91cc\u7684\u7528\u6237<\/p>\n

<\/span><\/p>\n

\u65b0\u5217\u8868\u91cc\u7684\u7528\u6237<\/p>\n

<\/span><\/p>\n

id \u662f\u5426\u4e00\u6837<\/p>\n

<\/span><\/p>\n

\u5185\u5bb9\u662f\u5426\u4e00\u6837<\/p>\n

<\/span><\/p>\n

\u4e0d\u662f\u540c\u4e00\u6761：\u63d2\u5165\u6216\u5220\u9664<\/p>\n

<\/span><\/p>\n

\u540c\u4e00\u6761\u4e14\u5185\u5bb9\u6ca1\u53d8：\u4e0d\u7528\u5237\u65b0<\/p>\n

<\/span><\/p>\n

\u540c\u4e00\u6761\u4f46\u5185\u5bb9\u53d8\u4e86：\u5237\u65b0\u8fd9\u4e00\u9879<\/p>\n

<\/span><\/p>\n

\u8fd9\u5c31\u662f\u975e\u5e38\u5178\u578b\u7684\u201c\u540c\u4e00\u4e2a\u201d\u548c\u201c\u5185\u5bb9\u4e00\u6837\u201d\u5206\u5f00\u5224\u65ad\u3002<\/p>\n

Kotlin data class<\/h4>\n

Kotlin \u91cc\u7684 data class \u4f1a\u81ea\u52a8\u751f\u6210 equals() \u548c hashCode()：<\/p>\n

data<\/span> class<\/span> User<\/span>(<\/span>
\n val<\/span> id:<\/span> Long,<\/span>
\n val<\/span> name:<\/span> String
\n)<\/span><\/p>\n

\u8fd9\u5f88\u65b9\u4fbf\u3002\u4f46\u4e5f\u8981\u6ce8\u610f：<\/p>\n

data class \u9ed8\u8ba4\u4f1a\u628a\u4e3b\u6784\u9020\u91cc\u7684\u5b57\u6bb5\u90fd\u62ff\u53bb\u6bd4\u8f83\u3002<\/p>\n

\u5982\u679c\u4f60\u5728\u5217\u8868\u91cc\u5224\u65ad\u201c\u662f\u4e0d\u662f\u540c\u4e00\u6761\u6570\u636e\u201d，\u901a\u5e38\u53ea\u5e94\u8be5\u770b id\u3002
\n\u5982\u679c\u4f60\u5224\u65ad\u201c\u5185\u5bb9\u6709\u6ca1\u6709\u53d8\u201d，\u624d\u66f4\u9002\u5408\u6bd4\u8f83\u6574\u4e2a\u5bf9\u8c61\u3002<\/p>\n

13. \u4e3a\u4ec0\u4e48\u9762\u8bd5\u5b98\u8fd9\u4e48\u7231\u95ee\u8fd9\u4e2a<\/h3>\n

\u56e0\u4e3a\u8fd9\u4e2a\u95ee\u9898\u8868\u9762\u5f88\u5c0f，\u5b9e\u9645\u53ef\u4ee5\u770b\u51fa\u5f88\u591a\u4e1c\u897f\u3002<\/p>\n\n\u9762\u8bd5\u5b98\u7ee7\u7eed\u95ee\u4ed6\u60f3\u770b\u4ec0\u4e48<\/tr>\n\n\n\n\n\n\n\n\n
== \u548c equals() \u533a\u522b<\/td>\n\u4f60\u61c2\u4e0d\u61c2\u5f15\u7528\u548c\u5bf9\u8c61<\/td>\n<\/tr>\n
Object.equals() \u9ed8\u8ba4\u505a\u4ec0\u4e48<\/td>\n\u4f60\u6709\u6ca1\u6709\u770b\u8fc7\u57fa\u7840\u6e90\u7801<\/td>\n<\/tr>\n
String \u4e3a\u4ec0\u4e48\u53ef\u4ee5\u6bd4\u8f83\u5185\u5bb9<\/td>\n\u4f60\u77e5\u4e0d\u77e5\u9053\u7c7b\u53ef\u4ee5\u91cd\u5199\u89c4\u5219<\/td>\n<\/tr>\n
\u4e3a\u4ec0\u4e48\u8fd8\u8981 hashCode()<\/td>\n\u4f60\u61c2\u4e0d\u61c2 HashMap \/ HashSet<\/td>\n<\/tr>\n
\u53ea\u5199 equals() \u4f1a\u600e\u6837<\/td>\n\u4f60\u6709\u6ca1\u6709\u8e29\u8fc7\u96c6\u5408\u7684\u5751<\/td>\n<\/tr>\n
\u5bf9\u8c61\u5b57\u6bb5\u53d8\u4e86\u4f1a\u600e\u6837<\/td>\n\u4f60\u6709\u6ca1\u6709\u771f\u5b9e\u5de5\u7a0b\u7ecf\u9a8c<\/td>\n<\/tr>\n
DiffUtil \u600e\u4e48\u5199<\/td>\n\u4f60\u80fd\u4e0d\u80fd\u628a Java \u57fa\u7840\u7528\u5230 Android \u91cc<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u8bf4\u767d\u4e86，\u5b83\u4e0d\u662f\u5728\u95ee\u4f60\u4f1a\u4e0d\u4f1a\u80cc equals()，\u800c\u662f\u5728\u770b\u4f60\u6709\u6ca1\u6709\u628a\u201c\u5bf9\u8c61\u3001\u96c6\u5408\u3001\u4e1a\u52a1\u8eab\u4efd\u201d\u8fd9\u4e09\u4ef6\u4e8b\u8fde\u8d77\u6765\u3002<\/p>\n

14. \u9762\u8bd5\u65f6\u600e\u4e48\u7b54\u6700\u987a<\/h3>\n

\u4f60\u53ef\u4ee5\u8fd9\u6837\u8bf4：<\/p>\n

\u5224\u65ad\u4e24\u4e2a\u5bf9\u8c61\u662f\u5426\u76f8\u540c，\u8981\u5148\u770b\u76f8\u540c\u7684\u542b\u4e49\u3002<\/p>\n

\u5982\u679c\u662f\u5224\u65ad\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61，\u7528 ==\u3002
\n\u56e0\u4e3a == \u6bd4\u8f83\u7684\u662f\u5f15\u7528\u5730\u5740\u3002<\/p>\n

\u5982\u679c\u662f\u5224\u65ad\u5185\u5bb9\u662f\u5426\u76f8\u540c，\u7528 equals\u3002
\n\u4f46\u666e\u901a\u7c7b\u9ed8\u8ba4 equals \u5176\u5b9e\u4e5f\u662f this == obj，
\n\u6240\u4ee5\u9700\u8981\u6839\u636e\u4e1a\u52a1\u91cd\u5199 equals\u3002<\/p>\n

\u5982\u679c\u5bf9\u8c61\u8981\u653e\u8fdb HashMap \u6216 HashSet，
\n\u8fd8\u5fc5\u987b\u91cd\u5199 hashCode\u3002
\n\u56e0\u4e3a HashMap \u4f1a\u5148\u7528 hashCode \u627e\u6876，
\n\u518d\u7528 == \u6216 equals \u5224\u65ad\u662f\u4e0d\u662f\u540c\u4e00\u4e2a key\u3002<\/p>\n

\u6240\u4ee5 equals \u76f8\u7b49\u7684\u5bf9\u8c61，hashCode \u5fc5\u987b\u76f8\u540c\u3002
\n\u4f46 hashCode \u76f8\u540c，\u4e0d\u4e00\u5b9a equals \u76f8\u540c\u3002<\/p>\n

\u66f4\u53e3\u8bed\u4e00\u70b9：<\/p>\n

\u6211\u4e00\u822c\u4f1a\u5148\u95ee\u6e05\u695a\u8fd9\u4e2a\u201c\u76f8\u540c\u201d\u6307\u4ec0\u4e48\u3002\u5982\u679c\u53ea\u662f\u4e24\u4e2a\u53d8\u91cf\u662f\u4e0d\u662f\u6307\u7740\u540c\u4e00\u4e2a\u5bf9\u8c61，\u90a3\u5c31\u662f ==\u3002\u5982\u679c\u662f\u4e24\u4e2a\u7528\u6237\u662f\u4e0d\u662f\u4e1a\u52a1\u4e0a\u7684\u540c\u4e00\u4e2a\u7528\u6237，\u5c31\u770b equals() \u600e\u4e48\u5b9a\u4e49，\u6bd4\u5982\u7528\u7528\u6237 id \u6765\u6bd4\u8f83\u3002\u4f46\u53ea\u8981\u8fd9\u4e2a\u5bf9\u8c61\u8981\u653e\u5230 HashMap \u6216 HashSet \u91cc，\u5c31\u4e0d\u80fd\u53ea\u5199 equals()，\u8fd8\u8981\u5199 hashCode()\u3002\u56e0\u4e3a\u54c8\u5e0c\u96c6\u5408\u662f\u5148\u6839\u636e hash \u627e\u6876，\u518d\u5728\u6876\u91cc\u7528 equals() \u786e\u8ba4\u3002\u5426\u5219\u4e24\u4e2a\u4e1a\u52a1\u4e0a\u76f8\u7b49\u7684\u5bf9\u8c61\u53ef\u80fd\u88ab\u653e\u5230\u4e0d\u540c\u6876\u91cc，\u5bfc\u81f4\u53bb\u91cd\u5931\u8d25\u6216\u8005\u67e5\u4e0d\u5230\u3002<\/p>\n

\u8fd9\u4e2a\u56de\u7b54\u5df2\u7ecf\u591f\u5e94\u4ed8\u5927\u591a\u6570\u8ffd\u95ee\u3002<\/p>\n

15. \u51e0\u4e2a\u5e38\u89c1\u5c0f\u9898<\/h3>\n

\u9898\u76ee\u4e00<\/h4>\n

String<\/span> a =<\/span> new<\/span> String<\/span>(<\/span>"x"<\/span>)<\/span>;<\/span>
\nString<\/span> b =<\/span> new<\/span> String<\/span>(<\/span>"x"<\/span>)<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a ==<\/span> b)<\/span>;<\/span>
\nSystem<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a.<\/span>equals<\/span>(<\/span>b)<\/span>)<\/span>;<\/span><\/p>\n

\u7b54\u6848：<\/p>\n

false
\ntrue<\/p>\n

\u56e0\u4e3a a \u548c b \u662f\u4e24\u4e2a\u5bf9\u8c61，\u6240\u4ee5 == \u662f false\u3002\u5b83\u4eec\u6587\u5b57\u5185\u5bb9\u4e00\u6837，\u6240\u4ee5 equals() \u662f true\u3002<\/p>\n

\u9898\u76ee\u4e8c<\/h4>\n

Integer<\/span> a =<\/span> 127<\/span>;<\/span>
\nInteger<\/span> b =<\/span> 127<\/span>;<\/span>
\nInteger<\/span> c =<\/span> 128<\/span>;<\/span>
\nInteger<\/span> d =<\/span> 128<\/span>;<\/span><\/p>\n

System<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>a ==<\/span> b)<\/span>;<\/span>
\nSystem<\/span>.<\/span>out.<\/span>println<\/span>(<\/span>c ==<\/span> d)<\/span>;<\/span><\/p>\n

\u5e38\u89c1\u7ed3\u679c：<\/p>\n

true
\nfalse<\/p>\n

\u4f46\u4f60\u4e0d\u8981\u8bb0\u6210\u201c127 \u7528 ==，128 \u4e0d\u884c\u201d\u3002\u6b63\u786e\u7406\u89e3\u662f：\u5305\u88c5\u7c7b\u578b\u6bd4\u8f83\u6570\u503c\u522b\u4f9d\u8d56 ==，\u8981\u7528 equals() \u6216\u62c6\u7bb1\u6bd4\u8f83\u3002<\/p>\n

\u9898\u76ee\u4e09<\/h4>\n

Set<\/span><<\/span>User<\/span>><\/span><\/span> set =<\/span> new<\/span> HashSet<\/span><<\/span>><\/span><\/span>(<\/span>)<\/span>;<\/span>
\nset.<\/span>add<\/span>(<\/span>new<\/span> User<\/span>(<\/span>1<\/span>)<\/span>)<\/span>;<\/span>
\nset.<\/span>add<\/span>(<\/span>new<\/span> User<\/span>(<\/span>1<\/span>)<\/span>)<\/span>;<\/span><\/p>\n

\u4e3a\u4ec0\u4e48\u53ef\u80fd\u6709\u4e24\u4e2a？<\/p>\n

\u56e0\u4e3a User \u53ef\u80fd\u53ea\u5199\u4e86 equals()，\u6ca1\u5199 hashCode()\u3002\u4e24\u4e2a\u5bf9\u8c61\u4e1a\u52a1\u4e0a\u76f8\u7b49，\u4f46\u53bb\u4e86\u4e0d\u540c\u6876，\u6240\u4ee5\u96c6\u5408\u6ca1\u6cd5\u53bb\u91cd\u3002<\/p>\n

16. \u6700\u540e\u603b\u7ed3<\/h3>\n

\u8fd9\u9053\u9898\u5176\u5b9e\u4e00\u53e5\u8bdd\u5c31\u80fd\u6536\u4f4f：<\/p>\n

== \u770b\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u5bf9\u8c61；
\nequals \u770b\u4e1a\u52a1\u4e0a\u662f\u4e0d\u662f\u76f8\u7b49；
\nhashCode \u5e2e\u54c8\u5e0c\u96c6\u5408\u5148\u627e\u5230\u8be5\u53bb\u54ea\u513f\u67e5\u3002<\/p>\n

\u522b\u628a\u5b83\u4eec\u6df7\u6210\u4e00\u4e2a\u4e1c\u897f\u3002\u4f60\u53ea\u8981\u80fd\u8bf4\u6e05\u201c\u6211\u73b0\u5728\u5224\u65ad\u7684\u662f\u54ea\u4e00\u79cd\u76f8\u540c\u201d，\u518d\u8bb2\u51fa HashMap \u4e3a\u4ec0\u4e48\u8981\u540c\u65f6\u4f9d\u8d56 hashCode() \u548c equals()，\u8fd9\u9898\u5c31\u4e0d\u662f\u5751，\u800c\u662f\u4e00\u4e2a\u5f88\u597d\u7684\u52a0\u5206\u70b9\u3002<\/p>\n

\u6700\u540e\u6211\u7684\u5efa\u8bae\u662f，\u5148\u628a\u6982\u5ff5\u56de\u7b54\u4e0a\u6765，\u518d\u53bb\u7528\u81ea\u5df1\u7684\u8bdd\u4ea7\u51fa\u76f8\u5e94\u7684\u7406\u89e3，\u4e0e\u9762\u8bd5\u5b98\u4ea7\u751f\u5171\u9e23\u70b9，\u90a3\u4e48\u5c31\u5bb9\u6613\u5f97\u5206，\u5426\u5219，\u57fa\u7840\u6982\u5ff5\u4e0d\u7262\u9760，\u4eba\u5bb6\u5c31\u6ca1\u6709\u88ab\u95ee\u4e0b\u53bb\u7684\u610f\u613f\u4e86，\u5c31\u975e\u5e38\u5bb9\u6613\u5931\u5206\u7684\u3002AI\u65f6\u4ee3\u4e0b，\u73b0\u5728\u7684\u9762\u8bd5\u771f\u7684\u8ddf\u5343\u519b\u4e07\u9a6c\u8fc7\u72ec\u6728\u6865\u4e00\u6837，\u4f60\u4e0d\u591f\u4f18\u79c0，\u54ea\u6015\u6709\u4e00\u4e01\u70b9\u56de\u7b54\u5730\u4e0d\u591f\u5230\u4f4d，\u5c31\u5bb9\u6613\u88ab\u6a2a\u5411\u5bf9\u6bd4\u3002\u8fd9\u4e5f\u662f\u6211\u4eec\u4e3a\u4ec0\u4e48\u8fd8\u9700\u8981\u5b66\u8fd9\u4e48\u57fa\u7840\u7684，\u662f49\u5e74\u5165\u56fd\u519b\u5417，\u6070\u6070\u4e0d\u662f，\u6211\u4eec\u8981\u5728\u8fd9\u4e2a\u65f6\u4ee3\u7ad9\u7a33\u811a\u8ddf，\u662f\u9700\u8981\u53bb\u6253\u7262\u8fd9\u4e9b\u57fa\u7840\u6839\u57fa\u7684\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

\u7b14\u8005\u53bb\u9762\u8bd5\u7684\u65f6\u5019，\u9762\u8bd5\u5b98\u51b7\u4e0d\u4e01\u5730\u95ee\u201cJava\u4e2d\u4e24\u4e2a\u5bf9\u8c61\u600e\u4e48\u5224\u65ad\u662f\u4e0d\u662f\u540c\u4e00\u4e2a\u201d，\u7b2c\u4e00\u53cd\u5e94\u5c31\u662f\u7b54：\u7528 equals()\u3002\u8fd9\u4e2a\u56de\u7b54\u4e0d\u80fd\u8bf4\u9519，\u90a3\u8fd8\u9700\u8981\u91cd\u5199\u4ec0\u4e48\u65b9\u6cd5，\u4e3a\u4ec0\u4e48，\u5f88\u5bb9\u6613\u88ab\u7ee7\u7eed\u8ffd\u95ee\u5230\u53d1\u61f5\u3002\u56e0\u4e3a\u9762\u8bd5\u5b98\u771f\u6b63\u60f3\u95ee\u7684\u662f：\u4f60\u8bf4\u7684\u201c\u540c\u4e00\u4e2a\u201d，\u5230\u5e95\u662f\u5730\u5740\u4e00\u6837\u3001\u5185\u5bb9\u4e00\u6837，\u8fd8\u662f\u653e\u8fdb HashMap \u91cc\u4e5f\u80fd\u88ab\u5f53\u6210\u540c\u4e00\u4e2a key？\u4e00\u53e5\u8bdd\u7ed3\u8bba： <\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[11653,84],"topic":[],"class_list":["post-107482","post","type-post","status-publish","format-standard","hentry","category-server","tag-11653","tag-android"],"yoast_head":"\n\u4e3a\u4ec0\u4e48\u9762\u8bd5\u5b98\u603b\u7231\u95eeJava\u4e2d\u600e\u4e48\u5224\u65ad\u4e24\u4e2a\u5bf9\u8c61\u662f\u76f8\u540c\u7684 - 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