1.1.java\u7684\u7279\u5b9a\u6709\u54ea\u4e9b？<\/h3>\n\n- \u5e73\u53f0\u65e0\u5173\u6027："\u4e00\u6b21\u7f16\u8bd1\u7ec8\u8eab\u8fd0\u884c"，\u5c31\u662f\u8bf4java\u7f16\u8bd1\u5668\u4f1a\u5c06\u6e90\u4ee3\u7801\u5148\u7f16\u8bd1\u6210\u5b57\u8282\u7801（\u4e0d\u540c\u673a\u5668\u4e0a\u53ea\u8981\u6e90\u4ee3\u7801\u76f8\u540c，\u90a3\u4e48\u5c31\u5b57\u8282\u7801\u4e00\u5b9a\u76f8\u540c），\u7136\u540eJVM\u4f1a\u5c06\u5b57\u8282\u7801\u7ffb\u8bd1\u6210\u5bf9\u5e94\u7684\u673a\u5668\u7801（JVM\u6709\u4e0d\u540c\u7cfb\u7edf\u7684\u7248\u672c，JVM\u4f1a\u6839\u636e\u4f60\u7684\u73af\u5883\u8fdb\u884c\u7ffb\u8bd1），\u603b\u7684\u6765\u8bf4\u5c31\u662f\u5b57\u8282\u7801\u4fdd\u8bc1\u7f16\u8bd1\u4e00\u81f4，\u7136\u540e\u6839\u636e\u4e0d\u540c\u7684JVM\u7ffb\u8bd1\u5bf9\u5e94\u673a\u5668\u7801<\/li>\n
- \u9762\u5411\u5bf9\u8c61：java\u662f\u4e00\u4e2a\u9762\u5411\u5bf9\u8c61\u7684\u8bed\u8a00，\u66f4\u65b9\u4fbf\u4ee3\u7801\u7684\u7ef4\u62a4\u548c\u4f7f\u7528<\/li>\n
- \u5185\u5b58\u7ba1\u7406：java\u62e5\u6709\u5783\u573e\u56de\u6536\u673a\u5236，\u5f00\u53d1\u4eba\u5458\u4e0d\u9700\u8981\u81ea\u5df1\u624b\u52a8\u5220\u9664\u5185\u5b58（\u4e0d\u9700\u8981\u8003\u8651\u8fd9\u4e48\u591a），\u7531\u5783\u573e\u56de\u6536\u673a\u5236\u6765\u81ea\u52a8\u5b9e\u73b0\u5185\u5b58\u91ca\u653e<\/li>\n<\/ul>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/05\/20250526023303-6833d2df5af36.png\")
<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/05\/20250526023303-6833d2df925c5.png\")
<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/05\/20250526023303-6833d2dfbcbfc.png\")
<\/p>\n
1.2.java\u6709\u54ea\u4e9b\u4f18\u52bf\u54ea\u4e9b\u52a3\u52bf？<\/h3>\n
\u4f18\u52bf：（\u7279\u5b9a\u90a3\u91cc）<\/p>\n
\n- \u8de8\u5e73\u53f0：java\u6709\u5e73\u53f0\u65e0\u5173\u6027<\/li>\n
- \u5185\u5b58\u7ba1\u7406：\u62e5\u6709\u5783\u573e\u56de\u6536\u673a\u5236<\/li>\n
- \u9762\u5411\u5bf9\u8c61：\u4f7f\u4ee3\u7801\u66f4\u597d\u7ef4\u62a4\u548c\u4f7f\u7528<\/li>\n
- \u5f3a\u5927\u7684\u751f\u6001\u7cfb\u7edf：\u5982Spring\u5168\u5bb6\u6876，\u5176\u4ed6\u7684\u5de5\u5177\u5305\u7b49\u7b49<\/li>\n
- \u7a33\u5b9a\u6027：\u652f\u6301\u4f01\u4e1a\u957f\u671f\u4f7f\u7528，\u7248\u672c\u5411\u540e\u517c\u5bb9<\/li>\n<\/ul>\n
\n\u52a3\u52bf：<\/p>\n
\n- \u5185\u5b58\u6d88\u8017\u5927：JVM\u865a\u62df\u673a\u672c\u8eab\u5c31\u9700\u8981\u4e00\u5b9a\u7684\u5185\u5b58<\/li>\n
- \u542f\u52a8\u65f6\u95f4\u957f：\u7531\u4e8e\u9700\u8981JVM\u5c06\u5b57\u8282\u7801\u7ffb\u8bd1\u6210\u673a\u5668\u7801<\/li>\n
- \u4ee3\u7801\u590d\u6742：\u7531\u4e8ejava\u8fc7\u4e8e\u9762\u5411\u5bf9\u8c61，\u4e00\u4e2a\u7b80\u5355\u7684\u7a0b\u5e8f\u7684\u4ee3\u7801\u590d\u6742（\u9ebb\u70e6）<\/li>\n<\/ul>\n
1.3.java\u4e3a\u4ec0\u4e48\u53ef\u4ee5\u8de8\u5e73\u53f0？<\/h3>\n
java\u5728\u7f16\u8bd1\u65f6，java\u7f16\u8bd1\u5668\u4f1a\u76f4\u63a5\u5c06\u6e90\u4ee3\u7801\u7f16\u5199\u6210\u5b57\u8282\u7801\u6587\u4ef6，\u7b49\u5230\u4f60\u9700\u8981\u8fd0\u884c\u65f6，\u4f1a\u6839\u636e\u4f60\u7684JVM\u865a\u62df\u673a\u7248\u672c\u4e0d\u540c，\u7136\u540e\u901a\u8fc7\u4e0d\u540c\u7684JVM\u5c06\u5b57\u8282\u7801\u7ffb\u8bd1\u6210\u673a\u5668\u7801（\u8ba9\u673a\u5668\u8bc6\u522b）<\/p>\n
1.4JVM,JDK,JRE\u5b83\u4eec\u6709\u4ec0\u4e48\u533a\u522b？<\/h3>\n
JVM：JVM\u662fjava\u865a\u62df\u673a，\u662fjava\u7a0b\u5e8f\u8fd0\u884c\u7684\u73af\u5883<\/p>\n
JDK：JDK\u662fjava\u7684\u4e00\u4e2a\u5f00\u53d1\u5de5\u5177\u5305（\u5404\u79cd\u7c7b，\u5de5\u5177）<\/p>\n
JRE：JRE\u662fjava\u8fd0\u884c\u7684\u73af\u5883，\u662fjava\u7a0b\u5e8f\u6240\u9700\u7684\u6700\u5c0f\u73af\u5883<\/p>\n<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/05\/20250526023303-6833d2dfd7f30.png\")
<\/p>\n
1.5.\u7f16\u8bd1\u578b\u8bed\u8a00\u4e0e\u89e3\u91ca\u578b\u8bed\u8a00\u7684\u533a\u522b？<\/h3>\n
\u7f16\u8bd1\u578b：\u5728\u8fd0\u884c\u4e4b\u524d\u9700\u8981\u7f16\u8bd1，\u5c06\u6e90\u4ee3\u7801\u7f16\u5199\u6210\u5b57\u8282\u7801\u6216\u8005\u673a\u5668\u7801（C++），\u5982\u679c\u5b83\u7f16\u5199\u6210\u673a\u5668\u7801，\u5728\u672c\u673a\u4e0a\u53ef\u4ee5\u76f4\u63a5\u8bc6\u522b\u673a\u5668\u7801，\u4ece\u800c\u5b83\u7684\u8fd0\u884c\u901f\u5ea6\u5feb，\u8de8\u5e73\u53f0\u6027\u5dee<\/p>\n
\u89e3\u91ca\u6027：\u4e0d\u9700\u8981\u7f16\u8bd1，\u5b83\u4f1a\u5728\u8fd0\u884c\u65f6\u9010\u884c\u89e3\u91ca\u4ee3\u7801，\u56e0\u8fd0\u884c\u901f\u5ea6\u6162，\u8de8\u5e73\u53f0\u6027\u597d<\/p>\n
2.\u6570\u636e\u7c7b\u578b<\/h2>\n2.1.long\u4e0eint\u7c7b\u578b\u53ef\u4ee5\u4e92\u8f6c\u5417？<\/h3>\n
\u53ef\u4ee5：\u4f46\u662f\u4f60\u9700\u8981\u8003\u8651\u6570\u636e\u7684\u6ea2\u51fa\u4e0e\u4e22\u5931<\/p>\n
\u6bd4\u5982：\u4f60\u5c06long\u7c7b\u578b\u8f6c\u6210int\u7c7b\u578b，\u5982\u679c\u4f60\u7684long\u7c7b\u578b\u7684\u6570\u5f88\u5927，\u5927\u5230int\u65e0\u6cd5\u5168\u90e8\u63a5\u6536，\u90a3\u4e48\u5c31\u4f1a\u51fa\u73b0\u6570\u636e\u7684\u4e22\u5931<\/p>\n
\u6bd4\u5982：\u4f60\u5c06int\u7c7b\u578b\u8f6c\u6210long\u7c7b\u578b，\u5982\u679c\u4f60\u7684int\u7c7b\u578b\u7684\u6570\u5f88\u5c0f，\u90a3\u4e48\u7528long\u63a5\u6536，\u7531\u4e8elong\u7cbe\u5ea6\u5927，\u5176\u4ed6\u4f4d\u5c06\u75280\u586b\u5145，\u51fa\u73b0\u6570\u636e\u6ea2\u51fa<\/p>\n
public class TypeConversion {
\n public static void main(String[] args) {
\n long bigLong = 2147483648L; \/\/ \u8d85\u51fa int \u6700\u5927\u503c（2147483647）
\n int intValue = (int) bigLong; \/\/ \u5f3a\u5236\u8f6c\u6362<\/p>\n
System.out.println("\u539f\u59cb long \u503c: " + bigLong); \/\/ \u8f93\u51fa 2147483648
\n System.out.println("\u8f6c\u6362\u540e\u7684 int \u503c: " + intValue); \/\/ \u8f93\u51fa -2147483648（\u6ea2\u51fa）
\n }
\n} <\/p>\n
2.2.\u6570\u636e\u7c7b\u578b\u8f6c\u53d8\u5f62\u5f0f\u6709\u54ea\u4e9b？<\/h3>\n
\u81ea\u52a8\u7c7b\u578b\u8f6c\u6362（\u9690\u5f0f\u8f6c\u6362）：\u5047\u5982：\u4f60\u4f7f\u7528long\u7c7b\u578b\u4e0eint\u7c7b\u578b\u8fdb\u884c\u76f8\u52a0，\u5b83\u4f1a\u9ed8\u8ba4\u5c06int\u7c7b\u578b\u9690\u5f0f\u8f6c\u6362\u6210long，\u518d\u8fdb\u884c\u8fd0\u7b97<\/p>\n
public class AutoConversion {
\n public static void main(String[] args) {
\n int a = 10;
\n long b = 20L;
\n long result = a + b; \/\/ int \u81ea\u52a8\u63d0\u5347\u4e3a long<\/p>\n
System.out.println(result); \/\/ \u8f93\u51fa 30
\n }
\n} <\/p>\n
\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362（\u663e\u793a\u8f6c\u6362）：\u5047\u5982：\u4f60\u4f7f\u7528long\u7c7b\u578b\u4e0eint\u7c7b\u578b\u8fdb\u884c\u76f8\u52a0，\u90a3\u4e48\u6700\u540e\u7684\u7ed3\u679c\u53ea\u80fd\u7528long\u7c7b\u578b\u63a5\u6536，\u5982\u679c\u4f60\u60f3\u8981\u4f7f\u7528int\u7c7b\u578b\u63a5\u6536，\u90a3\u4e48\u9700\u8981\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362<\/p>\n
public class ForceConversion {
\n public static void main(String[] args) {
\n long a = 2147483648L; \/\/ \u8d85\u8fc7 int \u6700\u5927\u503c（2147483647）
\n int b = (int) a; \/\/ \u5f3a\u5236\u8f6c\u6362<\/p>\n
System.out.println(b); \/\/ \u8f93\u51fa -2147483648（\u9ad8\u4f4d\u622a\u65ad）
\n }
\n} <\/p>\n
\u5b57\u7b26\u4e32\u8f6c\u6362：\u4f7f\u7528\u5305\u88c5\u7c7b\u91cc\u9762\u7684\u65b9\u6cd5\u8fdb\u884c\u8f6c\u6362，\u6bd4\u5982：\u4f60\u5c06char\u7c7b\u578b\u8f6c\u6362\u6210int，\u90a3\u4e48\u5b83\u4f1a\u6839\u636eASCII\u7801\u5bf9\u5e94\u8868\u8f6c\u6210\u5bf9\u5e94\u6570<\/p>\n
public class StringConversion {
\n public static void main(String[] args) {
\n \/\/ 1. \u5b57\u7b26\u4e32 \u2192 \u6570\u503c\u7c7b\u578b（\u9700\u5904\u7406\u5f02\u5e38）
\n String str = "123";
\n int num = Integer.parseInt(str); \/\/ \u5b57\u7b26\u4e32\u8f6c int
\n double d = Double.parseDouble(str); \/\/ \u5b57\u7b26\u4e32\u8f6c double<\/p>\n
\/\/ 2. \u6570\u503c\u7c7b\u578b \u2192 \u5b57\u7b26\u4e32
\n String s1 = Integer.toString(num); \/\/ \u65b9\u6cd51
\n String s2 = String.valueOf(d); \/\/ \u65b9\u6cd52
\n String s3 = "" + num; \/\/ \u65b9\u6cd53（\u9690\u5f0f\u8f6c\u6362）<\/p>\n
\/\/ 3. char \u2192 int（ASCII \u7801\u8f6c\u6362）
\n char c = 'A';
\n int ascii = c; \/\/ \u76f4\u63a5\u8d4b\u503c，\u8f93\u51fa 65
\n int numericValue = Character.getNumericValue('9'); \/\/ \u8f93\u51fa 9
\n }
\n} <\/p>\n
2.3.\u7c7b\u578b\u8f6c\u6362\u4f1a\u51fa\u73b0\u54ea\u4e9b\u95ee\u9898？<\/h3>\n
\u6570\u636e\u4e22\u5931：\u5c0f\u7c7b\u578b\u8f6c\u5927\u7c7b\u578b（\u7cbe\u5ea6\u4e0d\u540c，\u9020\u6210\u6570\u636e\u4e22\u5931）<\/p>\n
\u6570\u636e\u6ea2\u51fa：\u5927\u7c7b\u578b\u8f6c\u5c0f\u7c7b\u578b（\u9ad8\u4f4d\u5168\u75280\u586b\u5145）<\/p>\n
\u7cbe\u5ea6\u4e0d\u540c：float\u662f\u5355\u7cbe\u5ea6，double\u662f\u53cc\u7cbe\u5ea6，\u4e24\u8005\u8f6c\u6362\u7cbe\u5ea6\u4f1a\u51fa\u73b0\u4e22\u5931<\/p>\n
\u7c7b\u578b\u4e0d\u540c：\u4e0d\u540c\u7c7b\u578b\u7684\u8f6c\u6362\u4f1a\u51fa\u73b0\u7f16\u8bd1\u9519\u8bef<\/p>\n
2.4.\u4e3a\u4ec0\u4e48\u7528bigDecimal \u4e0d\u7528double？<\/h3>\n
\u4e3e\u4f8b：\u4f60\u80fd\u4f7f\u7528\u5341\u8fdb\u5236\u8868\u793a1\/3\u5417？\u65e0\u6cd5\u8868\u793a，\u4e00\u76f4\u5728\u5faa\u73af，\u800cdouble\u662f\u8fdb\u884c\u4e8c\u8fdb\u5236\u8fd0\u7b97\u7684，\u6bd4\u5982：0.1\u4f60\u80fd\u4f7f\u7528\u4e8c\u8fdb\u5236\u8fdb\u884c\u8868\u793a\u5417？\u4e5f\u662f\u4e00\u76f4\u5faa\u73af，\u800cdouble\u662f\u6709\u7cbe\u5ea6\u7684，\u5230\u8fbe\u5b83\u7684\u7cbe\u5ea6\u9650\u5ea6\u540e，\u5b83\u4e0d\u4f1a\u5728\u5faa\u73af\u4e0b\u53bb，\u56e0\u6b64\u4f1a\u51fa\u73b0\u7cbe\u5ea6\u4e22\u5931\u95ee\u9898<\/p>\n
\u89e3\u51b3：\u4f7f\u7528bigDecimal（\u6ce8\u610f：\u5982\u679c\u4f60\u8fd8\u662f\u4f7f\u7528\u6d6e\u70b9\u6570\u8d4b\u503c\u7ed9\u5b83，\u8fd8\u662f\u4f1a\u51fa\u73b0\u8be5\u95ee\u9898（\u9ed8\u8ba4\u6d6e\u70b9\u6570\u5c31\u662fdouble\u7c7b\u578b），\u56e0\u6b64\u4f7f\u7528\u5b57\u7b26\u4e32\u8d4b\u503c）<\/p>\n
System.out.println(0.1 + 0.2); \/\/ \u8f93\u51fa 0.30000000000000004（\u7cbe\u5ea6\u4e22\u5931）
\nimport java.math.BigDecimal;<\/p>\n
public class BadExample {
\n public static void main(String[] args) {
\n BigDecimal a = new BigDecimal(0.1); \/\/ \u7528 double \u521d\u59cb\u5316（\u9519\u8bef！）
\n BigDecimal b = new BigDecimal(0.2);
\n BigDecimal result = a.add(b);<\/p>\n
System.out.println(result); \/\/ \u8f93\u51fa 0.3000000000000000166533453694…
\n }
\n}
\nimport java.math.BigDecimal;<\/p>\n
public class GoodExample {
\n public static void main(String[] args) {
\n BigDecimal a = new BigDecimal("0.1"); \/\/ \u7528\u5b57\u7b26\u4e32\u521d\u59cb\u5316（\u6b63\u786e！）
\n BigDecimal b = new BigDecimal("0.2");
\n BigDecimal result = a.add(b);<\/p>\n
System.out.println(result); \/\/ \u8f93\u51fa 0.3
\n }
\n} <\/p>\n
2.5.\u88c5\u7bb1\u4e0e\u62c6\u7bb1\u4f1a\u51fa\u73b0\u4ec0\u4e48\u95ee\u9898？<\/h3>\n
\u88c5\u7bb1：\u5c31\u662f\u5c06\u57fa\u672c\u7c7b\u578b\u5305\u88c5\u6210\u5305\u88c5\u7c7b<\/p>\n
\u62c6\u7bb1：\u5c31\u662f\u5c06\u5305\u88c5\u7c7b\u62c6\u6210\u57fa\u672c\u7c7b\u578b<\/p>\n
\u95ee\u9898：\u7531\u4e8ejava\u53ef\u4ee5\u5b9e\u73b0\u81ea\u52a8\u88c5\u7bb1\u4e0e\u62c6\u7bb1，\u5982\u679c\u4f60\u5b9a\u4e49\u4e00\u4e2aInteger\u7c7b\u578b，\u4f46\u662f\u6ca1\u6709\u7ed9\u5b83\u8d4b\u503c，\u5b83\u4f1a\u9ed8\u8ba4null，\u7136\u540e\u5c06\u5b83\u62c6\u7bb1，\u4f46\u662fnull\u503c\u662f\u65e0\u6cd5\u62c6\u7bb1\u7684，\u56e0\u6b64\u4f1a\u51fa\u73b0\u7a7a\u6307\u9488\u5f02\u5e38<\/span><\/p>\n2.6.Integer\u4e3a\u4ec0\u4e48\u4f1a\u5b58\u5728\u4e00\u4e2a\u7f13\u5b58\u6c60？<\/h3>\n
\u7531\u4e8e\u6211\u4eec\u9700\u8981\u4f7f\u7528\u5bf9\u5e94\u7684\u5305\u88c5\u7c7b，\u4f46\u662f\u6bcf\u6b21\u90fd\u9700\u8981\u91cd\u65b0\u521b\u5efa\u5bf9\u8c61（\u6d88\u8017\u5185\u5b58），\u5e76\u4e14\u8fdb\u884c\u4e00\u4e2a\u8fd0\u7b97\u5c31\u4f1a\u521b\u5efa\u4e00\u4e2a\u5bf9\u8c61（\u65e0\u5173\u5185\u5b58），\u56e0\u6b64\u4e3a\u4e86\u8282\u7701\u5185\u5b58，java\u5c06\u6211\u4eec\u5e38\u4f7f\u7528\u7684-128\u5230127\u7684\u5bf9\u8c61\u5df2\u7ecf\u521b\u5efa\u597d\u4e86，\u653e\u5728\u9759\u6001\u7f13\u5b58\u6c60\u4e2d，\u4f60\u4f7f\u7528.valueInt()\u8fd9\u4e2a\u65b9\u6cd5\u8fdb\u884c\u8d4b\u503c，\u5b83\u5c31\u4f1a\u53bb\u590d\u7528\u6c60\u4e2d\u5bf9\u8c61（\u5730\u5740\u76f8\u540c）<\/p>\n
Integer a = Integer.valueOf(100); \/\/ \u4ece\u7f13\u5b58\u6c60\u83b7\u53d6（\u5730\u5740\u76f8\u540c）
\nInteger b = 100; \/\/ \u9690\u5f0f\u8c03\u7528 valueOf()，\u590d\u7528\u7f13\u5b58
\nInteger c = new Integer(100); \/\/ \u5f3a\u5236\u521b\u5efa\u65b0\u5bf9\u8c61（\u5730\u5740\u4e0d\u540c）<\/p>\n
System.out.println(a == b); \/\/ true（\u540c\u4e00\u5bf9\u8c61）
\nSystem.out.println(a == c); \/\/ false（\u4e0d\u540c\u5bf9\u8c61） <\/p>\n
3.\u9762\u5411\u5bf9\u8c61<\/h2>\n3.1.\u600e\u4e48\u7406\u89e3\u9762\u5411\u5bf9\u8c61？<\/h3>\n
\u9762\u5411\u5bf9\u8c61\u5c31\u662f\u5c06\u73b0\u5b9e\u751f\u6d3b\u4e2d\u7684\u5404\u4e2a\u4e8b\u52a1\u62bd\u8c61\u6210\u5bf9\u8c61<\/p>\n
3.2.\u8bf4\u4e00\u4e0b\u5c01\u88c5\u7ee7\u627f\u591a\u6001？<\/h3>\n
\u5c01\u88c5：\u5c31\u662f\u5c06\u5171\u6027\u7684\u5c5e\u6027\u4e0e\u65b9\u6cd5\u5c01\u88c5\u5230\u7c7b\u4e2d，\u9690\u85cf\u7c7b\u4e2d\u7684\u7ec6\u8282，\u4ec5\u66b4\u9732\u51fa\u4f60\u60f3\u8981\u66b4\u9732\u7684\u63a5\u53e3\u6765\u4e0e\u5916\u754c\u4ea4\u4e92，\u589e\u52a0\u4e86\u4ee3\u7801\u7684\u5b89\u5168\u6027\u548c\u6269\u5c55\u6027<\/p>\n
\u7ee7\u627f：\u5b50\u7c7b\u5171\u4eab\u7236\u7c7b\u7684\u5c5e\u6027\u4e0e\u65b9\u6cd5，\u662f\u4ee3\u7801\u5b9e\u73b0\u590d\u7528，\u5efa\u7acb\u4e86\u7c7b\u4e0e\u7c7b\u4e4b\u95f4\u7684\u8054\u7cfb，\u662f\u7c7b\u4e4b\u95f4\u7684\u7ed3\u6784\u66f4\u52a0\u6e05\u6670<\/p>\n
\u591a\u6001：\u4e0d\u540c\u7c7b\u5bf9\u5e94\u4e0d\u540c\u6d88\u606f\u7684\u4e0d\u540c\u64cd\u4f5c\u65b9\u5f0f，\u662f\u4ee3\u7801\u66f4\u52a0\u7075\u6d3b<\/p>\n
3.3.\u591a\u6001\u4f53\u73b0\u5728\u54ea\u51e0\u4e2a\u65b9\u9762？<\/h3>\n
\u65b9\u6cd5\u91cd\u8f7d：\u540c\u4e00\u4e2a\u7c7b\u53ef\u4ee5\u6709\u591a\u4e2a\u65b9\u6cd5\u540d\u76f8\u540c\u7684\u65b9\u6cd5（\u53c2\u6570\u4e0d\u540c）<\/p>\n
\u65b9\u6cd5\u91cd\u5199：\u5b50\u7c7b\u91cd\u5199\u7236\u7c7b\u7684\u65b9\u6cd5<\/p>\n
\u63a5\u53e3\u5b9e\u73b0：\u4e0d\u540c\u7684\u7c7b\u5b9e\u73b0\u540c\u4e00\u4e2a\u63a5\u53e3，\u90a3\u4e48\u521b\u5efa\u5bf9\u8c61\u65f6，\u53ef\u4ee5\u4f7f\u7528\u63a5\u53e3\u521b\u5efa，\u8c03\u7528\u65b9\u5f0f\u4e00\u81f4<\/p>\n
\u5411\u4e0a\u4e0e\u5411\u4e0b\u8f6c\u578b：\u5411\u4e0a：\u7236\u7c7b\u8f6c\u5b50\u7c7b\u00a0 \u00a0\u5411\u4e0b：\u5b50\u7c7b\u8f6c\u7236\u7c7b<\/p>\n
3.4.\u91cd\u5199\u4e0e\u91cd\u8f7d\u7684\u533a\u522b？<\/h3>\n
\u91cd\u5199：\u5b50\u7c7b\u91cd\u5199\u7236\u7c7b\u65b9\u6cd5，\u9700\u8981\u4e0e\u7236\u7c7b\u65b9\u6cd5\u540d，\u8fd4\u56de\u7c7b\u578b，\u53c2\u6570\u4fdd\u6301\u4e00\u81f4，\u53ea\u80fd\u4fee\u6539\u5176\u5185\u90e8\u7684\u4ee3\u7801<\/p>\n
\u91cd\u8f7d：\u5728\u540c\u4e00\u4e2a\u7c7b\u4e2d\u4f60\u53ef\u4ee5\u91cd\u8f7d\u591a\u4e2a\u65b9\u6cd5\u540d\u76f8\u540c\u7684\u65b9\u6cd5，\u4f46\u662f\u533a\u522b\u5728\u4e8e\u53c2\u6570\u4e0d\u540c（1.\u53c2\u6570\u7c7b\u578b\u4e0d\u540c，2.\u53c2\u6570\u6570\u91cf\u4e0d\u540c，3.\u53c2\u6570\u987a\u5e8f\u4e0d\u540c），\u6ee1\u8db3\u4e00\u4e2a\u5373\u53ef<\/p>\n
3.5.\u62bd\u8c61\u7c7b\u4e0e\u666e\u901a\u7c7b\u7684\u533a\u522b？<\/h3>\n
\u5b9e\u4f8b\u5316：\u62bd\u8c61\u7c7b\u4e0d\u53ef\u4ee5\u5b9e\u4f8b\u5316，\u666e\u901a\u7c7b\u53ef\u4ee5<\/p>\n
—–<\/p>\n
\u65b9\u6cd5\u5b9e\u73b0：\u62bd\u8c61\u7c7b\u65b9\u6cd5\u53ef\u4ee5\u5b9e\u73b0\u53ef\u4ee5\u53ea\u5b9a\u4e49，\u800c\u666e\u901a\u7c7b\u9700\u8981\u5177\u4f53\u7684\u65b9\u6cd5\u5b9e\u73b0<\/p>\n
3.6.\u62bd\u8c61\u7c7b\u4e0e\u63a5\u53e3\u7684\u533a\u522b？<\/h3>\n
\u5b9e\u73b0\u65b9\u5f0f：\u62bd\u8c61\u7c7b\u9700\u8981\u7ee7\u627fextends，\u63a5\u53e3\u9700\u8981\u5b9e\u73b0implements<\/p>\n
—–<\/p>\n
\u8bbf\u95ee\u4fee\u9970\u7b26\u4e0d\u540c：\u4e24\u8005\u7684\u5c5e\u6027\u4e0e\u65b9\u6cd5\u9ed8\u8ba4\u4fee\u9970\u7b26\u4e0d\u540c<\/p>\n
—–<\/p>\n
\u65b9\u6cd5\u5b9e\u73b0\u4e0d\u540c：\u62bd\u8c61\u7c7b\u65b9\u6cd5\u53ef\u4ee5\u5b9a\u4e49\u53ef\u4ee5\u5b9e\u73b0，\u63a5\u53e3\u53ea\u80fd\u5b9a\u4e49<\/p>\n
—–<\/p>\n
\u53d8\u91cf：\u62bd\u8c61\u7c7b\u53ef\u4ee5\u6709\u5b9e\u4f8b\u53d8\u91cf\u548c\u9759\u6001\u53d8\u91cf，\u800c\u63a5\u53e3\u53ea\u6709\u9759\u6001\u53d8\u91cf<\/p>\n
—–<\/p>\n
\u7279\u70b9：\u63a5\u53e3\u662f\u5b9a\u4e49\u7c7b\u7684\u529f\u80fd\u6216\u884c\u4e3a，\u62bd\u8c61\u7c7b\u662f\u63cf\u8ff0\u7c7b\u7684\u5171\u6027\u548c\u884c\u4e3a\u7684<\/p>\n
3.7.\u62bd\u8c61\u7c7b\u53ef\u4ee5\u52a0final\u5173\u952e\u5b57\u5417？<\/h3>\n
\u4e0d\u53ef\u4ee5，\u62bd\u8c61\u7c7b\u672c\u8eab\u5c31\u662f\u4e00\u4e2a\u57fa\u7c7b\u5c31\u662f\u8ba9\u5176\u4ed6\u7c7b\u7ee7\u627f\u7684，\u800c\u7c7b\u52a0\u4e0afinal\u4f1a\u8ba9\u8be5\u7c7b\u65e0\u6cd5\u88ab\u7ee7\u627f<\/p>\n
\u56e0\u6b64\u4e24\u8005\u4e92\u65a5<\/p>\n
3.8.\u89e3\u91ca\u4e00\u4e0b\u9759\u6001\u53d8\u91cf\u4e0e\u9759\u6001\u65b9\u6cd5？<\/h3>\n
\u9759\u6001\u7684\u4e1c\u897f\u53ea\u6709\u5f53\u7c7b\u52a0\u8f7d\u5b8c\u540e，\u5b83\u5c31\u4f1a\u52a0\u8f7d，\u53ea\u4f1a\u5728\u5185\u5b58\u4e2d\u52a0\u8f7d\u4e00\u6b21<\/p>\n
3.9.\u4e3a\u4ec0\u4e48\u9759\u6001\u4e0d\u80fd\u8c03\u7528\u975e\u9759\u6001？<\/h3>\n
\u9759\u6001\u53ea\u6709\u5f53\u7c7b\u52a0\u8f7d\u5b8c\u5c31\u4f1a\u52a0\u8f7d，\u56e0\u6b64\u9759\u6001\u4f1a\u4f18\u5148\u4e8e\u975e\u9759\u6001\u52a0\u8f7d（\u9700\u8981\u5b9e\u4f8b\u5316），\u4f60\u4e00\u4e2a\u6ca1\u52a0\u8f7d\u7684\u600e\u4e48\u80fd\u88ab\u8c03\u7528\u5462？<\/p>\n
\u6bd4\u5982：\u9759\u6001\u65b9\u6cd5\u91cc\u9762\u8c03\u7528\u975e\u9759\u6001\u65b9\u6cd5，\u6211\u9759\u6001\u65b9\u6cd5\u90fd\u5df2\u7ecf\u52a0\u8f7d\u5b8c\u4e86，\u800c\u4f60\u975e\u9759\u6001\u65b9\u6cd5\u5fc5\u987b\u8981\u5b9e\u4f8b\u5316\u624d\u80fd\u52a0\u8f7d，\u6ca1\u6709\u5b9e\u4f8b\u5316\u4e0d\u52a0\u8f7d，\u90a3\u4e48\u6211\u600e\u4e48\u8c03\u7528\u4f60\u5462？（\u4e0d\u80fd\u786e\u5b9a\u975e\u9759\u6001\u662f\u5426\u52a0\u8f7d）<\/p>\n
\u6bd4\u5982：\u53cd\u8fc7\u6765，\u5c31\u53ef\u4ee5\u89e3\u91ca\u4e3a\u4ec0\u4e48\u975e\u9759\u6001\u53ef\u4ee5\u8c03\u7528\u9759\u6001，\u56e0\u4e3a\u975e\u9759\u6001\u52a0\u8f7d\u6162，\u5b83\u52a0\u8f7d\u5b8c\u5c31\u4e00\u5b9a\u6709\u9759\u6001\u52a0\u8f7d\u5b8c，\u56e0\u6b64\u53ef\u4ee5\u8c03\u7528<\/p>\n
public class Example {
\n static int staticVar = 10; \/\/ \u7c7b\u52a0\u8f7d\u65f6\u521d\u59cb\u5316
\n int instanceVar = 20; \/\/ \u5bf9\u8c61\u5b9e\u4f8b\u5316\u65f6\u521d\u59cb\u5316
\n}
\npublic class Example {
\n static void staticMethod() {
\n instanceMethod(); \/\/ \u7f16\u8bd1\u9519\u8bef：\u65e0\u6cd5\u8c03\u7528\u975e\u9759\u6001\u65b9\u6cd5
\n System.out.println(instanceVar); \/\/ \u7f16\u8bd1\u9519\u8bef：\u65e0\u6cd5\u8bbf\u95ee\u975e\u9759\u6001\u53d8\u91cf
\n }<\/p>\n
void instanceMethod() {
\n System.out.println("\u975e\u9759\u6001\u65b9\u6cd5");
\n }
\n}
\npublic class Example {
\n static int staticVar = 10;<\/p>\n
void instanceMethod() {
\n System.out.println(staticVar); \/\/ \u5408\u6cd5：\u9759\u6001\u6210\u5458\u5df2\u52a0\u8f7d
\n staticMethod(); \/\/ \u5408\u6cd5：\u9759\u6001\u65b9\u6cd5\u5df2\u52a0\u8f7d
\n }<\/p>\n
static void staticMethod() {
\n System.out.println("\u9759\u6001\u65b9\u6cd5");
\n }
\n} <\/p>\n
3.10.\u4e3a\u4ec0\u4e48\u975e\u9759\u6001\u5185\u90e8\u7c7b\u53ef\u4ee5\u8bbf\u95ee\u5916\u90e8\u7c7b？<\/h3>\n
\u5c31\u662f\u5f53\u5916\u90e8\u7c7b\u5b9e\u4f8b\u5316\u540e，\u4f1a\u5c06\u5916\u90e8\u7c7b\u7684\u5b9e\u4f8b\u5316\u5730\u5740（\u5f15\u7528）\u5f53\u4f5c\u53c2\u6570\u4f20\u7ed9\u975e\u9759\u6001\u5185\u90e8\u7c7b，\u56e0\u6b64\u5b83\u53ef\u4ee5\u6839\u636e\u5f15\u7528\u6765\u8bbf\u95ee<\/p>\n
4.\u5173\u952e\u5b57<\/h2>\n4.1.final<\/h3>\n
\n\n\n\u4fee\u9970\u7c7b<\/td>\n \u4ee3\u8868\u7c7b\u4e0d\u80fd\u88ab\u7ee7\u627f<\/td>\n<\/tr>\n \n\u4fee\u9970\u65b9\u6cd5<\/td>\n \u4ee3\u8868\u65b9\u6cd5\u4e0d\u80fd\u88ab\u91cd\u5199<\/td>\n<\/tr>\n \n\u4fee\u9970\u53d8\u91cf<\/td>\n \u5982\u679c\u662f\u57fa\u672c\u7c7b\u578b，\u503c\u4e0d\u80fd\u88ab\u4fee\u6539，\u662f\u5f15\u7528\u7c7b\u578b，\u503c\u53ef\u4ee5\u88ab\u4fee\u6539，\u5730\u5740\u4e0d\u80fd\u4fee\u6539<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":"\u6587\u7ae0\u6d4f\u89c8\u9605\u8bfb3.8k\u6b21\uff0c\u70b9\u8d5e68\u6b21\uff0c\u6536\u85cf70\u6b21\u3002\u6587\u7ae0\u4eceJava\u5e73\u53f0\u65e0\u5173\u6027\u3001\u9762\u5411\u5bf9\u8c61\u7279\u6027\u548c\u5185\u5b58\u7ba1\u7406\u4e09\u5927\u7279\u5f81\u5165\u624b\uff0c\u7cfb\u7edf\u4ecb\u7ecd\u4e86Java\u7684\u4f18\u52bf\u4e0e\u52a3\u52bf\u3002\u6df1\u5165\u8bb2\u89e3\u4e86\u6570\u636e\u7c7b\u578b\u8f6c\u6362\u3001BigDecimal\u7cbe\u5ea6\u5904\u7406\u3001\u88c5\u7bb1\u62c6\u7bb1\u95ee\u9898\u53caInteger\u7f13\u5b58\u6c60\u673a\u5236\u3002\u5728\u9762\u5411\u5bf9\u8c61\u90e8\u5206\uff0c\u8be6\u7ec6\u9610\u8ff0\u4e86\u5c01\u88c5\u3001\u7ee7\u627f\u3001\u591a\u6001\u4e09\u5927\u7279\u6027\uff0c\u5206\u6790\u4e86\u91cd\u5199\u4e0e\u91cd\u8f7d\u3001\u62bd\u8c61\u7c7b\u4e0e\u63a5\u53e3\u7684\u533a\u522b\uff0c\u5e76\u89e3\u91ca\u4e86\u9759\u6001\u6210\u5458\u4e0e\u975e\u9759\u6001\u6210\u5458\u7684\u8c03\u7528\u89c4\u5219\u3002\u6700\u540e\u8ba8\u8bba\u4e86final\u5173\u952e\u5b57\u7684\u7528\u6cd5\u3002\u5168\u6587\u901a\u8fc7\u4ee3\u7801\u793a\u4f8b\u8bf4\u660e\u5173\u952e\u6982\u5ff5\uff0c\u5e2e\u52a9\u8bfb\u8005\u5168\u9762\u7406\u89e3Java\u6838\u5fc3\u673a\u5236\u3002<\/p>\n","protected":false},"author":2,"featured_media":39847,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[99,190,305,2757],"topic":[],"class_list":["post-39851","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-java","tag-190","tag-305","tag-2757"],"yoast_head":"\n
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<\/p>\n
<\/p>\n
<\/p>\n
1.2.java\u6709\u54ea\u4e9b\u4f18\u52bf\u54ea\u4e9b\u52a3\u52bf？<\/h3>\n
\u4f18\u52bf：（\u7279\u5b9a\u90a3\u91cc）<\/p>\n
- \n
- \u8de8\u5e73\u53f0：java\u6709\u5e73\u53f0\u65e0\u5173\u6027<\/li>\n
- \u5185\u5b58\u7ba1\u7406：\u62e5\u6709\u5783\u573e\u56de\u6536\u673a\u5236<\/li>\n
- \u9762\u5411\u5bf9\u8c61：\u4f7f\u4ee3\u7801\u66f4\u597d\u7ef4\u62a4\u548c\u4f7f\u7528<\/li>\n
- \u5f3a\u5927\u7684\u751f\u6001\u7cfb\u7edf：\u5982Spring\u5168\u5bb6\u6876，\u5176\u4ed6\u7684\u5de5\u5177\u5305\u7b49\u7b49<\/li>\n
- \u7a33\u5b9a\u6027：\u652f\u6301\u4f01\u4e1a\u957f\u671f\u4f7f\u7528，\u7248\u672c\u5411\u540e\u517c\u5bb9<\/li>\n<\/ul>\n
\n\u52a3\u52bf：<\/p>\n
- \n
- \u5185\u5b58\u6d88\u8017\u5927：JVM\u865a\u62df\u673a\u672c\u8eab\u5c31\u9700\u8981\u4e00\u5b9a\u7684\u5185\u5b58<\/li>\n
- \u542f\u52a8\u65f6\u95f4\u957f：\u7531\u4e8e\u9700\u8981JVM\u5c06\u5b57\u8282\u7801\u7ffb\u8bd1\u6210\u673a\u5668\u7801<\/li>\n
- \u4ee3\u7801\u590d\u6742：\u7531\u4e8ejava\u8fc7\u4e8e\u9762\u5411\u5bf9\u8c61，\u4e00\u4e2a\u7b80\u5355\u7684\u7a0b\u5e8f\u7684\u4ee3\u7801\u590d\u6742（\u9ebb\u70e6）<\/li>\n<\/ul>\n
1.3.java\u4e3a\u4ec0\u4e48\u53ef\u4ee5\u8de8\u5e73\u53f0？<\/h3>\n
java\u5728\u7f16\u8bd1\u65f6，java\u7f16\u8bd1\u5668\u4f1a\u76f4\u63a5\u5c06\u6e90\u4ee3\u7801\u7f16\u5199\u6210\u5b57\u8282\u7801\u6587\u4ef6，\u7b49\u5230\u4f60\u9700\u8981\u8fd0\u884c\u65f6，\u4f1a\u6839\u636e\u4f60\u7684JVM\u865a\u62df\u673a\u7248\u672c\u4e0d\u540c，\u7136\u540e\u901a\u8fc7\u4e0d\u540c\u7684JVM\u5c06\u5b57\u8282\u7801\u7ffb\u8bd1\u6210\u673a\u5668\u7801（\u8ba9\u673a\u5668\u8bc6\u522b）<\/p>\n
1.4JVM,JDK,JRE\u5b83\u4eec\u6709\u4ec0\u4e48\u533a\u522b？<\/h3>\n
JVM：JVM\u662fjava\u865a\u62df\u673a，\u662fjava\u7a0b\u5e8f\u8fd0\u884c\u7684\u73af\u5883<\/p>\n
JDK：JDK\u662fjava\u7684\u4e00\u4e2a\u5f00\u53d1\u5de5\u5177\u5305（\u5404\u79cd\u7c7b，\u5de5\u5177）<\/p>\n
JRE：JRE\u662fjava\u8fd0\u884c\u7684\u73af\u5883，\u662fjava\u7a0b\u5e8f\u6240\u9700\u7684\u6700\u5c0f\u73af\u5883<\/p>\n<\/p>\n
<\/p>\n1.5.\u7f16\u8bd1\u578b\u8bed\u8a00\u4e0e\u89e3\u91ca\u578b\u8bed\u8a00\u7684\u533a\u522b？<\/h3>\n
\u7f16\u8bd1\u578b：\u5728\u8fd0\u884c\u4e4b\u524d\u9700\u8981\u7f16\u8bd1，\u5c06\u6e90\u4ee3\u7801\u7f16\u5199\u6210\u5b57\u8282\u7801\u6216\u8005\u673a\u5668\u7801（C++），\u5982\u679c\u5b83\u7f16\u5199\u6210\u673a\u5668\u7801，\u5728\u672c\u673a\u4e0a\u53ef\u4ee5\u76f4\u63a5\u8bc6\u522b\u673a\u5668\u7801，\u4ece\u800c\u5b83\u7684\u8fd0\u884c\u901f\u5ea6\u5feb，\u8de8\u5e73\u53f0\u6027\u5dee<\/p>\n
\u89e3\u91ca\u6027：\u4e0d\u9700\u8981\u7f16\u8bd1，\u5b83\u4f1a\u5728\u8fd0\u884c\u65f6\u9010\u884c\u89e3\u91ca\u4ee3\u7801，\u56e0\u8fd0\u884c\u901f\u5ea6\u6162，\u8de8\u5e73\u53f0\u6027\u597d<\/p>\n
2.\u6570\u636e\u7c7b\u578b<\/h2>\n
2.1.long\u4e0eint\u7c7b\u578b\u53ef\u4ee5\u4e92\u8f6c\u5417？<\/h3>\n
\u53ef\u4ee5：\u4f46\u662f\u4f60\u9700\u8981\u8003\u8651\u6570\u636e\u7684\u6ea2\u51fa\u4e0e\u4e22\u5931<\/p>\n
\u6bd4\u5982：\u4f60\u5c06long\u7c7b\u578b\u8f6c\u6210int\u7c7b\u578b，\u5982\u679c\u4f60\u7684long\u7c7b\u578b\u7684\u6570\u5f88\u5927，\u5927\u5230int\u65e0\u6cd5\u5168\u90e8\u63a5\u6536，\u90a3\u4e48\u5c31\u4f1a\u51fa\u73b0\u6570\u636e\u7684\u4e22\u5931<\/p>\n
\u6bd4\u5982：\u4f60\u5c06int\u7c7b\u578b\u8f6c\u6210long\u7c7b\u578b，\u5982\u679c\u4f60\u7684int\u7c7b\u578b\u7684\u6570\u5f88\u5c0f，\u90a3\u4e48\u7528long\u63a5\u6536，\u7531\u4e8elong\u7cbe\u5ea6\u5927，\u5176\u4ed6\u4f4d\u5c06\u75280\u586b\u5145，\u51fa\u73b0\u6570\u636e\u6ea2\u51fa<\/p>\n
public class TypeConversion {
\n public static void main(String[] args) {
\n long bigLong = 2147483648L; \/\/ \u8d85\u51fa int \u6700\u5927\u503c（2147483647）
\n int intValue = (int) bigLong; \/\/ \u5f3a\u5236\u8f6c\u6362<\/p>\nSystem.out.println("\u539f\u59cb long \u503c: " + bigLong); \/\/ \u8f93\u51fa 2147483648
\n System.out.println("\u8f6c\u6362\u540e\u7684 int \u503c: " + intValue); \/\/ \u8f93\u51fa -2147483648（\u6ea2\u51fa）
\n }
\n} <\/p>\n2.2.\u6570\u636e\u7c7b\u578b\u8f6c\u53d8\u5f62\u5f0f\u6709\u54ea\u4e9b？<\/h3>\n
\u81ea\u52a8\u7c7b\u578b\u8f6c\u6362（\u9690\u5f0f\u8f6c\u6362）：\u5047\u5982：\u4f60\u4f7f\u7528long\u7c7b\u578b\u4e0eint\u7c7b\u578b\u8fdb\u884c\u76f8\u52a0，\u5b83\u4f1a\u9ed8\u8ba4\u5c06int\u7c7b\u578b\u9690\u5f0f\u8f6c\u6362\u6210long，\u518d\u8fdb\u884c\u8fd0\u7b97<\/p>\n
public class AutoConversion {
\n public static void main(String[] args) {
\n int a = 10;
\n long b = 20L;
\n long result = a + b; \/\/ int \u81ea\u52a8\u63d0\u5347\u4e3a long<\/p>\nSystem.out.println(result); \/\/ \u8f93\u51fa 30
\n }
\n} <\/p>\n\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362（\u663e\u793a\u8f6c\u6362）：\u5047\u5982：\u4f60\u4f7f\u7528long\u7c7b\u578b\u4e0eint\u7c7b\u578b\u8fdb\u884c\u76f8\u52a0，\u90a3\u4e48\u6700\u540e\u7684\u7ed3\u679c\u53ea\u80fd\u7528long\u7c7b\u578b\u63a5\u6536，\u5982\u679c\u4f60\u60f3\u8981\u4f7f\u7528int\u7c7b\u578b\u63a5\u6536，\u90a3\u4e48\u9700\u8981\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362<\/p>\n
public class ForceConversion {
\n public static void main(String[] args) {
\n long a = 2147483648L; \/\/ \u8d85\u8fc7 int \u6700\u5927\u503c（2147483647）
\n int b = (int) a; \/\/ \u5f3a\u5236\u8f6c\u6362<\/p>\nSystem.out.println(b); \/\/ \u8f93\u51fa -2147483648（\u9ad8\u4f4d\u622a\u65ad）
\n }
\n} <\/p>\n\u5b57\u7b26\u4e32\u8f6c\u6362：\u4f7f\u7528\u5305\u88c5\u7c7b\u91cc\u9762\u7684\u65b9\u6cd5\u8fdb\u884c\u8f6c\u6362，\u6bd4\u5982：\u4f60\u5c06char\u7c7b\u578b\u8f6c\u6362\u6210int，\u90a3\u4e48\u5b83\u4f1a\u6839\u636eASCII\u7801\u5bf9\u5e94\u8868\u8f6c\u6210\u5bf9\u5e94\u6570<\/p>\n
public class StringConversion {
\n public static void main(String[] args) {
\n \/\/ 1. \u5b57\u7b26\u4e32 \u2192 \u6570\u503c\u7c7b\u578b（\u9700\u5904\u7406\u5f02\u5e38）
\n String str = "123";
\n int num = Integer.parseInt(str); \/\/ \u5b57\u7b26\u4e32\u8f6c int
\n double d = Double.parseDouble(str); \/\/ \u5b57\u7b26\u4e32\u8f6c double<\/p>\n\/\/ 2. \u6570\u503c\u7c7b\u578b \u2192 \u5b57\u7b26\u4e32
\n String s1 = Integer.toString(num); \/\/ \u65b9\u6cd51
\n String s2 = String.valueOf(d); \/\/ \u65b9\u6cd52
\n String s3 = "" + num; \/\/ \u65b9\u6cd53（\u9690\u5f0f\u8f6c\u6362）<\/p>\n\/\/ 3. char \u2192 int（ASCII \u7801\u8f6c\u6362）
\n char c = 'A';
\n int ascii = c; \/\/ \u76f4\u63a5\u8d4b\u503c，\u8f93\u51fa 65
\n int numericValue = Character.getNumericValue('9'); \/\/ \u8f93\u51fa 9
\n }
\n} <\/p>\n2.3.\u7c7b\u578b\u8f6c\u6362\u4f1a\u51fa\u73b0\u54ea\u4e9b\u95ee\u9898？<\/h3>\n
\u6570\u636e\u4e22\u5931：\u5c0f\u7c7b\u578b\u8f6c\u5927\u7c7b\u578b（\u7cbe\u5ea6\u4e0d\u540c，\u9020\u6210\u6570\u636e\u4e22\u5931）<\/p>\n
\u6570\u636e\u6ea2\u51fa：\u5927\u7c7b\u578b\u8f6c\u5c0f\u7c7b\u578b（\u9ad8\u4f4d\u5168\u75280\u586b\u5145）<\/p>\n
\u7cbe\u5ea6\u4e0d\u540c：float\u662f\u5355\u7cbe\u5ea6，double\u662f\u53cc\u7cbe\u5ea6，\u4e24\u8005\u8f6c\u6362\u7cbe\u5ea6\u4f1a\u51fa\u73b0\u4e22\u5931<\/p>\n
\u7c7b\u578b\u4e0d\u540c：\u4e0d\u540c\u7c7b\u578b\u7684\u8f6c\u6362\u4f1a\u51fa\u73b0\u7f16\u8bd1\u9519\u8bef<\/p>\n
2.4.\u4e3a\u4ec0\u4e48\u7528bigDecimal \u4e0d\u7528double？<\/h3>\n
\u4e3e\u4f8b：\u4f60\u80fd\u4f7f\u7528\u5341\u8fdb\u5236\u8868\u793a1\/3\u5417？\u65e0\u6cd5\u8868\u793a，\u4e00\u76f4\u5728\u5faa\u73af，\u800cdouble\u662f\u8fdb\u884c\u4e8c\u8fdb\u5236\u8fd0\u7b97\u7684，\u6bd4\u5982：0.1\u4f60\u80fd\u4f7f\u7528\u4e8c\u8fdb\u5236\u8fdb\u884c\u8868\u793a\u5417？\u4e5f\u662f\u4e00\u76f4\u5faa\u73af，\u800cdouble\u662f\u6709\u7cbe\u5ea6\u7684，\u5230\u8fbe\u5b83\u7684\u7cbe\u5ea6\u9650\u5ea6\u540e，\u5b83\u4e0d\u4f1a\u5728\u5faa\u73af\u4e0b\u53bb，\u56e0\u6b64\u4f1a\u51fa\u73b0\u7cbe\u5ea6\u4e22\u5931\u95ee\u9898<\/p>\n
\u89e3\u51b3：\u4f7f\u7528bigDecimal（\u6ce8\u610f：\u5982\u679c\u4f60\u8fd8\u662f\u4f7f\u7528\u6d6e\u70b9\u6570\u8d4b\u503c\u7ed9\u5b83，\u8fd8\u662f\u4f1a\u51fa\u73b0\u8be5\u95ee\u9898（\u9ed8\u8ba4\u6d6e\u70b9\u6570\u5c31\u662fdouble\u7c7b\u578b），\u56e0\u6b64\u4f7f\u7528\u5b57\u7b26\u4e32\u8d4b\u503c）<\/p>\n
System.out.println(0.1 + 0.2); \/\/ \u8f93\u51fa 0.30000000000000004（\u7cbe\u5ea6\u4e22\u5931）
\nimport java.math.BigDecimal;<\/p>\npublic class BadExample {
\n public static void main(String[] args) {
\n BigDecimal a = new BigDecimal(0.1); \/\/ \u7528 double \u521d\u59cb\u5316（\u9519\u8bef！）
\n BigDecimal b = new BigDecimal(0.2);
\n BigDecimal result = a.add(b);<\/p>\nSystem.out.println(result); \/\/ \u8f93\u51fa 0.3000000000000000166533453694…
\n }
\n}
\nimport java.math.BigDecimal;<\/p>\npublic class GoodExample {
\n public static void main(String[] args) {
\n BigDecimal a = new BigDecimal("0.1"); \/\/ \u7528\u5b57\u7b26\u4e32\u521d\u59cb\u5316（\u6b63\u786e！）
\n BigDecimal b = new BigDecimal("0.2");
\n BigDecimal result = a.add(b);<\/p>\nSystem.out.println(result); \/\/ \u8f93\u51fa 0.3
\n }
\n} <\/p>\n2.5.\u88c5\u7bb1\u4e0e\u62c6\u7bb1\u4f1a\u51fa\u73b0\u4ec0\u4e48\u95ee\u9898？<\/h3>\n
\u88c5\u7bb1：\u5c31\u662f\u5c06\u57fa\u672c\u7c7b\u578b\u5305\u88c5\u6210\u5305\u88c5\u7c7b<\/p>\n
\u62c6\u7bb1：\u5c31\u662f\u5c06\u5305\u88c5\u7c7b\u62c6\u6210\u57fa\u672c\u7c7b\u578b<\/p>\n
\u95ee\u9898：\u7531\u4e8ejava\u53ef\u4ee5\u5b9e\u73b0\u81ea\u52a8\u88c5\u7bb1\u4e0e\u62c6\u7bb1，\u5982\u679c\u4f60\u5b9a\u4e49\u4e00\u4e2aInteger\u7c7b\u578b，\u4f46\u662f\u6ca1\u6709\u7ed9\u5b83\u8d4b\u503c，\u5b83\u4f1a\u9ed8\u8ba4null，\u7136\u540e\u5c06\u5b83\u62c6\u7bb1，\u4f46\u662fnull\u503c\u662f\u65e0\u6cd5\u62c6\u7bb1\u7684，\u56e0\u6b64\u4f1a\u51fa\u73b0\u7a7a\u6307\u9488\u5f02\u5e38<\/span><\/p>\n
2.6.Integer\u4e3a\u4ec0\u4e48\u4f1a\u5b58\u5728\u4e00\u4e2a\u7f13\u5b58\u6c60？<\/h3>\n
\u7531\u4e8e\u6211\u4eec\u9700\u8981\u4f7f\u7528\u5bf9\u5e94\u7684\u5305\u88c5\u7c7b，\u4f46\u662f\u6bcf\u6b21\u90fd\u9700\u8981\u91cd\u65b0\u521b\u5efa\u5bf9\u8c61（\u6d88\u8017\u5185\u5b58），\u5e76\u4e14\u8fdb\u884c\u4e00\u4e2a\u8fd0\u7b97\u5c31\u4f1a\u521b\u5efa\u4e00\u4e2a\u5bf9\u8c61（\u65e0\u5173\u5185\u5b58），\u56e0\u6b64\u4e3a\u4e86\u8282\u7701\u5185\u5b58，java\u5c06\u6211\u4eec\u5e38\u4f7f\u7528\u7684-128\u5230127\u7684\u5bf9\u8c61\u5df2\u7ecf\u521b\u5efa\u597d\u4e86，\u653e\u5728\u9759\u6001\u7f13\u5b58\u6c60\u4e2d，\u4f60\u4f7f\u7528.valueInt()\u8fd9\u4e2a\u65b9\u6cd5\u8fdb\u884c\u8d4b\u503c，\u5b83\u5c31\u4f1a\u53bb\u590d\u7528\u6c60\u4e2d\u5bf9\u8c61（\u5730\u5740\u76f8\u540c）<\/p>\n
Integer a = Integer.valueOf(100); \/\/ \u4ece\u7f13\u5b58\u6c60\u83b7\u53d6（\u5730\u5740\u76f8\u540c）
\nInteger b = 100; \/\/ \u9690\u5f0f\u8c03\u7528 valueOf()，\u590d\u7528\u7f13\u5b58
\nInteger c = new Integer(100); \/\/ \u5f3a\u5236\u521b\u5efa\u65b0\u5bf9\u8c61（\u5730\u5740\u4e0d\u540c）<\/p>\nSystem.out.println(a == b); \/\/ true（\u540c\u4e00\u5bf9\u8c61）
\nSystem.out.println(a == c); \/\/ false（\u4e0d\u540c\u5bf9\u8c61） <\/p>\n3.\u9762\u5411\u5bf9\u8c61<\/h2>\n
3.1.\u600e\u4e48\u7406\u89e3\u9762\u5411\u5bf9\u8c61？<\/h3>\n
\u9762\u5411\u5bf9\u8c61\u5c31\u662f\u5c06\u73b0\u5b9e\u751f\u6d3b\u4e2d\u7684\u5404\u4e2a\u4e8b\u52a1\u62bd\u8c61\u6210\u5bf9\u8c61<\/p>\n
3.2.\u8bf4\u4e00\u4e0b\u5c01\u88c5\u7ee7\u627f\u591a\u6001？<\/h3>\n
\u5c01\u88c5：\u5c31\u662f\u5c06\u5171\u6027\u7684\u5c5e\u6027\u4e0e\u65b9\u6cd5\u5c01\u88c5\u5230\u7c7b\u4e2d，\u9690\u85cf\u7c7b\u4e2d\u7684\u7ec6\u8282，\u4ec5\u66b4\u9732\u51fa\u4f60\u60f3\u8981\u66b4\u9732\u7684\u63a5\u53e3\u6765\u4e0e\u5916\u754c\u4ea4\u4e92，\u589e\u52a0\u4e86\u4ee3\u7801\u7684\u5b89\u5168\u6027\u548c\u6269\u5c55\u6027<\/p>\n
\u7ee7\u627f：\u5b50\u7c7b\u5171\u4eab\u7236\u7c7b\u7684\u5c5e\u6027\u4e0e\u65b9\u6cd5，\u662f\u4ee3\u7801\u5b9e\u73b0\u590d\u7528，\u5efa\u7acb\u4e86\u7c7b\u4e0e\u7c7b\u4e4b\u95f4\u7684\u8054\u7cfb，\u662f\u7c7b\u4e4b\u95f4\u7684\u7ed3\u6784\u66f4\u52a0\u6e05\u6670<\/p>\n
\u591a\u6001：\u4e0d\u540c\u7c7b\u5bf9\u5e94\u4e0d\u540c\u6d88\u606f\u7684\u4e0d\u540c\u64cd\u4f5c\u65b9\u5f0f，\u662f\u4ee3\u7801\u66f4\u52a0\u7075\u6d3b<\/p>\n
3.3.\u591a\u6001\u4f53\u73b0\u5728\u54ea\u51e0\u4e2a\u65b9\u9762？<\/h3>\n
\u65b9\u6cd5\u91cd\u8f7d：\u540c\u4e00\u4e2a\u7c7b\u53ef\u4ee5\u6709\u591a\u4e2a\u65b9\u6cd5\u540d\u76f8\u540c\u7684\u65b9\u6cd5（\u53c2\u6570\u4e0d\u540c）<\/p>\n
\u65b9\u6cd5\u91cd\u5199：\u5b50\u7c7b\u91cd\u5199\u7236\u7c7b\u7684\u65b9\u6cd5<\/p>\n
\u63a5\u53e3\u5b9e\u73b0：\u4e0d\u540c\u7684\u7c7b\u5b9e\u73b0\u540c\u4e00\u4e2a\u63a5\u53e3，\u90a3\u4e48\u521b\u5efa\u5bf9\u8c61\u65f6，\u53ef\u4ee5\u4f7f\u7528\u63a5\u53e3\u521b\u5efa，\u8c03\u7528\u65b9\u5f0f\u4e00\u81f4<\/p>\n
\u5411\u4e0a\u4e0e\u5411\u4e0b\u8f6c\u578b：\u5411\u4e0a：\u7236\u7c7b\u8f6c\u5b50\u7c7b\u00a0 \u00a0\u5411\u4e0b：\u5b50\u7c7b\u8f6c\u7236\u7c7b<\/p>\n
3.4.\u91cd\u5199\u4e0e\u91cd\u8f7d\u7684\u533a\u522b？<\/h3>\n
\u91cd\u5199：\u5b50\u7c7b\u91cd\u5199\u7236\u7c7b\u65b9\u6cd5，\u9700\u8981\u4e0e\u7236\u7c7b\u65b9\u6cd5\u540d，\u8fd4\u56de\u7c7b\u578b，\u53c2\u6570\u4fdd\u6301\u4e00\u81f4，\u53ea\u80fd\u4fee\u6539\u5176\u5185\u90e8\u7684\u4ee3\u7801<\/p>\n
\u91cd\u8f7d：\u5728\u540c\u4e00\u4e2a\u7c7b\u4e2d\u4f60\u53ef\u4ee5\u91cd\u8f7d\u591a\u4e2a\u65b9\u6cd5\u540d\u76f8\u540c\u7684\u65b9\u6cd5，\u4f46\u662f\u533a\u522b\u5728\u4e8e\u53c2\u6570\u4e0d\u540c（1.\u53c2\u6570\u7c7b\u578b\u4e0d\u540c，2.\u53c2\u6570\u6570\u91cf\u4e0d\u540c，3.\u53c2\u6570\u987a\u5e8f\u4e0d\u540c），\u6ee1\u8db3\u4e00\u4e2a\u5373\u53ef<\/p>\n
3.5.\u62bd\u8c61\u7c7b\u4e0e\u666e\u901a\u7c7b\u7684\u533a\u522b？<\/h3>\n
\u5b9e\u4f8b\u5316：\u62bd\u8c61\u7c7b\u4e0d\u53ef\u4ee5\u5b9e\u4f8b\u5316，\u666e\u901a\u7c7b\u53ef\u4ee5<\/p>\n
—–<\/p>\n
\u65b9\u6cd5\u5b9e\u73b0：\u62bd\u8c61\u7c7b\u65b9\u6cd5\u53ef\u4ee5\u5b9e\u73b0\u53ef\u4ee5\u53ea\u5b9a\u4e49，\u800c\u666e\u901a\u7c7b\u9700\u8981\u5177\u4f53\u7684\u65b9\u6cd5\u5b9e\u73b0<\/p>\n
3.6.\u62bd\u8c61\u7c7b\u4e0e\u63a5\u53e3\u7684\u533a\u522b？<\/h3>\n
\u5b9e\u73b0\u65b9\u5f0f：\u62bd\u8c61\u7c7b\u9700\u8981\u7ee7\u627fextends，\u63a5\u53e3\u9700\u8981\u5b9e\u73b0implements<\/p>\n
—–<\/p>\n
\u8bbf\u95ee\u4fee\u9970\u7b26\u4e0d\u540c：\u4e24\u8005\u7684\u5c5e\u6027\u4e0e\u65b9\u6cd5\u9ed8\u8ba4\u4fee\u9970\u7b26\u4e0d\u540c<\/p>\n
—–<\/p>\n
\u65b9\u6cd5\u5b9e\u73b0\u4e0d\u540c：\u62bd\u8c61\u7c7b\u65b9\u6cd5\u53ef\u4ee5\u5b9a\u4e49\u53ef\u4ee5\u5b9e\u73b0，\u63a5\u53e3\u53ea\u80fd\u5b9a\u4e49<\/p>\n
—–<\/p>\n
\u53d8\u91cf：\u62bd\u8c61\u7c7b\u53ef\u4ee5\u6709\u5b9e\u4f8b\u53d8\u91cf\u548c\u9759\u6001\u53d8\u91cf，\u800c\u63a5\u53e3\u53ea\u6709\u9759\u6001\u53d8\u91cf<\/p>\n
—–<\/p>\n
\u7279\u70b9：\u63a5\u53e3\u662f\u5b9a\u4e49\u7c7b\u7684\u529f\u80fd\u6216\u884c\u4e3a，\u62bd\u8c61\u7c7b\u662f\u63cf\u8ff0\u7c7b\u7684\u5171\u6027\u548c\u884c\u4e3a\u7684<\/p>\n
3.7.\u62bd\u8c61\u7c7b\u53ef\u4ee5\u52a0final\u5173\u952e\u5b57\u5417？<\/h3>\n
\u4e0d\u53ef\u4ee5，\u62bd\u8c61\u7c7b\u672c\u8eab\u5c31\u662f\u4e00\u4e2a\u57fa\u7c7b\u5c31\u662f\u8ba9\u5176\u4ed6\u7c7b\u7ee7\u627f\u7684，\u800c\u7c7b\u52a0\u4e0afinal\u4f1a\u8ba9\u8be5\u7c7b\u65e0\u6cd5\u88ab\u7ee7\u627f<\/p>\n
\u56e0\u6b64\u4e24\u8005\u4e92\u65a5<\/p>\n
3.8.\u89e3\u91ca\u4e00\u4e0b\u9759\u6001\u53d8\u91cf\u4e0e\u9759\u6001\u65b9\u6cd5？<\/h3>\n
\u9759\u6001\u7684\u4e1c\u897f\u53ea\u6709\u5f53\u7c7b\u52a0\u8f7d\u5b8c\u540e，\u5b83\u5c31\u4f1a\u52a0\u8f7d，\u53ea\u4f1a\u5728\u5185\u5b58\u4e2d\u52a0\u8f7d\u4e00\u6b21<\/p>\n
3.9.\u4e3a\u4ec0\u4e48\u9759\u6001\u4e0d\u80fd\u8c03\u7528\u975e\u9759\u6001？<\/h3>\n
\u9759\u6001\u53ea\u6709\u5f53\u7c7b\u52a0\u8f7d\u5b8c\u5c31\u4f1a\u52a0\u8f7d，\u56e0\u6b64\u9759\u6001\u4f1a\u4f18\u5148\u4e8e\u975e\u9759\u6001\u52a0\u8f7d（\u9700\u8981\u5b9e\u4f8b\u5316），\u4f60\u4e00\u4e2a\u6ca1\u52a0\u8f7d\u7684\u600e\u4e48\u80fd\u88ab\u8c03\u7528\u5462？<\/p>\n
\u6bd4\u5982：\u9759\u6001\u65b9\u6cd5\u91cc\u9762\u8c03\u7528\u975e\u9759\u6001\u65b9\u6cd5，\u6211\u9759\u6001\u65b9\u6cd5\u90fd\u5df2\u7ecf\u52a0\u8f7d\u5b8c\u4e86，\u800c\u4f60\u975e\u9759\u6001\u65b9\u6cd5\u5fc5\u987b\u8981\u5b9e\u4f8b\u5316\u624d\u80fd\u52a0\u8f7d，\u6ca1\u6709\u5b9e\u4f8b\u5316\u4e0d\u52a0\u8f7d，\u90a3\u4e48\u6211\u600e\u4e48\u8c03\u7528\u4f60\u5462？（\u4e0d\u80fd\u786e\u5b9a\u975e\u9759\u6001\u662f\u5426\u52a0\u8f7d）<\/p>\n
\u6bd4\u5982：\u53cd\u8fc7\u6765，\u5c31\u53ef\u4ee5\u89e3\u91ca\u4e3a\u4ec0\u4e48\u975e\u9759\u6001\u53ef\u4ee5\u8c03\u7528\u9759\u6001，\u56e0\u4e3a\u975e\u9759\u6001\u52a0\u8f7d\u6162，\u5b83\u52a0\u8f7d\u5b8c\u5c31\u4e00\u5b9a\u6709\u9759\u6001\u52a0\u8f7d\u5b8c，\u56e0\u6b64\u53ef\u4ee5\u8c03\u7528<\/p>\n
public class Example {
\n static int staticVar = 10; \/\/ \u7c7b\u52a0\u8f7d\u65f6\u521d\u59cb\u5316
\n int instanceVar = 20; \/\/ \u5bf9\u8c61\u5b9e\u4f8b\u5316\u65f6\u521d\u59cb\u5316
\n}
\npublic class Example {
\n static void staticMethod() {
\n instanceMethod(); \/\/ \u7f16\u8bd1\u9519\u8bef：\u65e0\u6cd5\u8c03\u7528\u975e\u9759\u6001\u65b9\u6cd5
\n System.out.println(instanceVar); \/\/ \u7f16\u8bd1\u9519\u8bef：\u65e0\u6cd5\u8bbf\u95ee\u975e\u9759\u6001\u53d8\u91cf
\n }<\/p>\nvoid instanceMethod() {
\n System.out.println("\u975e\u9759\u6001\u65b9\u6cd5");
\n }
\n}
\npublic class Example {
\n static int staticVar = 10;<\/p>\nvoid instanceMethod() {
\n System.out.println(staticVar); \/\/ \u5408\u6cd5：\u9759\u6001\u6210\u5458\u5df2\u52a0\u8f7d
\n staticMethod(); \/\/ \u5408\u6cd5：\u9759\u6001\u65b9\u6cd5\u5df2\u52a0\u8f7d
\n }<\/p>\nstatic void staticMethod() {
\n System.out.println("\u9759\u6001\u65b9\u6cd5");
\n }
\n} <\/p>\n3.10.\u4e3a\u4ec0\u4e48\u975e\u9759\u6001\u5185\u90e8\u7c7b\u53ef\u4ee5\u8bbf\u95ee\u5916\u90e8\u7c7b？<\/h3>\n
\u5c31\u662f\u5f53\u5916\u90e8\u7c7b\u5b9e\u4f8b\u5316\u540e，\u4f1a\u5c06\u5916\u90e8\u7c7b\u7684\u5b9e\u4f8b\u5316\u5730\u5740（\u5f15\u7528）\u5f53\u4f5c\u53c2\u6570\u4f20\u7ed9\u975e\u9759\u6001\u5185\u90e8\u7c7b，\u56e0\u6b64\u5b83\u53ef\u4ee5\u6839\u636e\u5f15\u7528\u6765\u8bbf\u95ee<\/p>\n
4.\u5173\u952e\u5b57<\/h2>\n
4.1.final<\/h3>\n
\n\n
\n \u4fee\u9970\u7c7b<\/td>\n \u4ee3\u8868\u7c7b\u4e0d\u80fd\u88ab\u7ee7\u627f<\/td>\n<\/tr>\n \n \u4fee\u9970\u65b9\u6cd5<\/td>\n \u4ee3\u8868\u65b9\u6cd5\u4e0d\u80fd\u88ab\u91cd\u5199<\/td>\n<\/tr>\n \n \u4fee\u9970\u53d8\u91cf<\/td>\n \u5982\u679c\u662f\u57fa\u672c\u7c7b\u578b，\u503c\u4e0d\u80fd\u88ab\u4fee\u6539，\u662f\u5f15\u7528\u7c7b\u578b，\u503c\u53ef\u4ee5\u88ab\u4fee\u6539，\u5730\u5740\u4e0d\u80fd\u4fee\u6539<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":" \u6587\u7ae0\u6d4f\u89c8\u9605\u8bfb3.8k\u6b21\uff0c\u70b9\u8d5e68\u6b21\uff0c\u6536\u85cf70\u6b21\u3002\u6587\u7ae0\u4eceJava\u5e73\u53f0\u65e0\u5173\u6027\u3001\u9762\u5411\u5bf9\u8c61\u7279\u6027\u548c\u5185\u5b58\u7ba1\u7406\u4e09\u5927\u7279\u5f81\u5165\u624b\uff0c\u7cfb\u7edf\u4ecb\u7ecd\u4e86Java\u7684\u4f18\u52bf\u4e0e\u52a3\u52bf\u3002\u6df1\u5165\u8bb2\u89e3\u4e86\u6570\u636e\u7c7b\u578b\u8f6c\u6362\u3001BigDecimal\u7cbe\u5ea6\u5904\u7406\u3001\u88c5\u7bb1\u62c6\u7bb1\u95ee\u9898\u53caInteger\u7f13\u5b58\u6c60\u673a\u5236\u3002\u5728\u9762\u5411\u5bf9\u8c61\u90e8\u5206\uff0c\u8be6\u7ec6\u9610\u8ff0\u4e86\u5c01\u88c5\u3001\u7ee7\u627f\u3001\u591a\u6001\u4e09\u5927\u7279\u6027\uff0c\u5206\u6790\u4e86\u91cd\u5199\u4e0e\u91cd\u8f7d\u3001\u62bd\u8c61\u7c7b\u4e0e\u63a5\u53e3\u7684\u533a\u522b\uff0c\u5e76\u89e3\u91ca\u4e86\u9759\u6001\u6210\u5458\u4e0e\u975e\u9759\u6001\u6210\u5458\u7684\u8c03\u7528\u89c4\u5219\u3002\u6700\u540e\u8ba8\u8bba\u4e86final\u5173\u952e\u5b57\u7684\u7528\u6cd5\u3002\u5168\u6587\u901a\u8fc7\u4ee3\u7801\u793a\u4f8b\u8bf4\u660e\u5173\u952e\u6982\u5ff5\uff0c\u5e2e\u52a9\u8bfb\u8005\u5168\u9762\u7406\u89e3Java\u6838\u5fc3\u673a\u5236\u3002<\/p>\n","protected":false},"author":2,"featured_media":39847,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[99,190,305,2757],"topic":[],"class_list":["post-39851","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-java","tag-190","tag-305","tag-2757"],"yoast_head":"\n
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