\n\n| JDK<\/td>\n | java.lang<\/td>\n | StringBuilder<\/td>\n | String<\/td>\n<\/tr>\n |
\n| JDK<\/td>\n | java.lang<\/td>\n | StringBuffer<\/td>\n | String（\u7ebf\u7a0b\u5b89\u5168）<\/td>\n<\/tr>\n |
\n| JDK<\/td>\n | java.util.stream<\/td>\n | Stream.Builder<\/td>\n | Stream<\/td>\n<\/tr>\n |
\n| JDK<\/td>\n | java.nio<\/td>\n | ByteBuffer<\/td>\n | \u5b57\u8282\u7f13\u51b2\u533a<\/td>\n<\/tr>\n |
\n| JDK<\/td>\n | java.util<\/td>\n | Locale.Builder<\/td>\n | Locale<\/td>\n<\/tr>\n |
\n| Spring<\/td>\n | Spring Web<\/td>\n | UriComponentsBuilder<\/td>\n | URI<\/td>\n<\/tr>\n |
\n| Spring<\/td>\n | Spring Web<\/td>\n | HttpHeaders<\/td>\n | HTTP \u5934<\/td>\n<\/tr>\n |
\n| MyBatis<\/td>\n | MyBatis<\/td>\n | SqlSessionFactoryBuilder<\/td>\n | SqlSessionFactory<\/td>\n<\/tr>\n |
\n| Lombok<\/td>\n | Lombok<\/td>\n | @Builder \u6ce8\u89e3<\/td>\n | \u4efb\u610f\u7c7b<\/td>\n<\/tr>\n |
\n| Guava<\/td>\n | Guava<\/td>\n | ImmutableList.builder()<\/td>\n | ImmutableList<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n \u6211\u4eec\u6309"JDK \u2192 Spring\/MyBatis"\u7684\u987a\u5e8f\u6765\u5256\u6790\u3002<\/p>\n
\n\u4e8c\u3001JDK \u6e90\u7801\u5256\u6790：3 \u4e2a\u7ecf\u5178\u5efa\u9020\u8005\u5b9e\u73b0<\/h3>\n2.1 StringBuilder \u2014\u2014 \u5b57\u7b26\u4e32\u62fc\u63a5\u7684"\u94fe\u5f0f\u5efa\u9020\u8005"<\/h4>\n\u6e90\u7801\u4f4d\u7f6e：<\/p>\n \n- OpenJDK 17<\/li>\n
- src\/java.base\/share\/classes\/java\/lang\/StringBuilder.java<\/li>\n<\/ul>\n
\u6838\u5fc3\u5b57\u6bb5：<\/p>\n public<\/span> final<\/span> class<\/span> StringBuilder<\/span> extends<\/span> AbstractStringBuilder<\/span>
\n implements<\/span> java.<\/span>io.<\/span><\/span>Serializable<\/span>,<\/span> Comparable<\/span><<\/span>StringBuilder<\/span>><\/span><\/span>,<\/span> CharSequence<\/span> {<\/span><\/p>\n \/**
\n * \u9ed8\u8ba4\u5bb9\u91cf
\n *\/<\/span>
\n static<\/span> final<\/span> int<\/span> DEFAULT_CAPACITY<\/span> =<\/span> 16<\/span>;<\/span>
\n}<\/span><\/p>\n\u6838\u5fc3\u65b9\u6cd5（\u7b80\u5316\u7248）：<\/p>\n \/**
\n * \u2705 \u94fe\u5f0f append：\u6bcf\u4e00\u6b65\u90fd\u8fd4\u56de this
\n *\/<\/span>
\n@Override<\/span>
\npublic<\/span> StringBuilder<\/span> append<\/span>(<\/span>Object<\/span> obj)<\/span> {<\/span>
\n return<\/span> append<\/span>(<\/span>String<\/span>.<\/span>valueOf<\/span>(<\/span>obj)<\/span>)<\/span>;<\/span>
\n}<\/span><\/p>\n@Override<\/span>
\npublic<\/span> StringBuilder<\/span> append<\/span>(<\/span>String<\/span> str)<\/span> {<\/span>
\n super<\/span>.<\/span>append<\/span>(<\/span>str)<\/span>;<\/span>
\n return<\/span> this<\/span>;<\/span>
\n}<\/span><\/p>\n@Override<\/span>
\npublic<\/span> StringBuilder<\/span> append<\/span>(<\/span>StringBuffer<\/span> sb)<\/span> {<\/span>
\n super<\/span>.<\/span>append<\/span>(<\/span>sb)<\/span>;<\/span>
\n return<\/span> this<\/span>;<\/span>
\n}<\/span><\/p>\n\/**
\n * \u2705 \u5de5\u5382\u65b9\u6cd5：build \u51fa\u6700\u7ec8 String
\n *\/<\/span>
\n@Override<\/span>
\npublic<\/span> String<\/span> toString<\/span>(<\/span>)<\/span> {<\/span>
\n \/\/ \u521b\u5efa\u65b0 String<\/span>
\n return<\/span> new<\/span> String<\/span>(<\/span>value,<\/span> 0<\/span>,<\/span> count)<\/span>;<\/span>
\n}<\/span><\/p>\n\u4e3a\u4ec0\u4e48 StringBuilder \u662f"\u5efa\u9020\u8005"？<\/p>\n - \u5206\u6b65\u6784\u9020：append() \u4e00\u6b21\u53c8\u4e00\u6b21\u5730"\u88c5\u90e8\u4ef6"<\/li>\n
- \u94fe\u5f0f\u8c03\u7528：\u6bcf\u4e2a append \u90fd\u8fd4\u56de this<\/li>\n
- \u4e0d\u53ef\u53d8\u7ed3\u679c：toString() \u4ea7\u51fa\u4e0d\u53ef\u53d8\u7684 String<\/li>\n
- \u534a\u6210\u54c1\u652f\u6301：StringBuilder \u672c\u8eab\u5c31\u662f\u534a\u6210\u54c1<\/li>\n
\u5b8c\u6574\u6d41\u7a0b：<\/p>\n StringBuilder builder = new StringBuilder();
\n \u2193 append("Hello")
\nbuilder = "Hello"
\n \u2193 append(" ")
\nbuilder = "Hello "
\n \u2193 append("World")
\nbuilder = "Hello World"
\n \u2193 toString()
\nresult = "Hello World" (\u65b0 String \u5bf9\u8c61)<\/p>\n \u4e3a\u4ec0\u4e48 StringBuilder \u662f"\u94fe\u5f0f"\u800c\u4e0d\u662f"\u5206\u6b65\u8d4b\u503c"？<\/p>\n \u56e0\u4e3a\u5b57\u7b26\u4e32\u6784\u9020\u662f\u9ad8\u9891\u64cd\u4f5c，\u9700\u8981\u6781\u81f4\u7684\u7b80\u6d01\u3002\u94fe\u5f0f\u8c03\u7528\u6bd4"\u5206\u6b65 + build()"\u5feb 50%\u3002<\/p>\n 2.2 Stream.Builder \u2014\u2014 \u6d41\u5f0f API \u7684"\u5efa\u9020\u8005"<\/h4>\n\u6e90\u7801\u4f4d\u7f6e：<\/p>\n \n- OpenJDK 17<\/li>\n
- src\/java.base\/share\/classes\/java\/util\/stream\/Stream.java<\/li>\n<\/ul>\n
\u6838\u5fc3\u6e90\u7801：<\/p>\n public<\/span> interface<\/span> Stream<\/span><<\/span>T<\/span>><\/span><\/span> extends<\/span> BaseStream<\/span><<\/span>T<\/span>,<\/span> Stream<\/span><<\/span>T<\/span>><\/span>><\/span><\/span> {<\/span><\/p>\n \/**
\n * \u2705 \u5185\u90e8 Builder \u63a5\u53e3
\n *\/<\/span>
\n interface<\/span> Builder<\/span><<\/span>T<\/span>><\/span><\/span> extends<\/span> Consumer<\/span><<\/span>T<\/span>><\/span><\/span> {<\/span>
\n @Override<\/span>
\n Builder<\/span><<\/span>T<\/span>><\/span><\/span> accept<\/span>(<\/span>T<\/span> t)<\/span>;<\/span> \/\/ \u6dfb\u52a0\u5143\u7d20<\/span><\/p>\n default<\/span> Builder<\/span><<\/span>T<\/span>><\/span><\/span> add<\/span>(<\/span>T<\/span> t)<\/span> {<\/span>
\n accept<\/span>(<\/span>t)<\/span>;<\/span>
\n return<\/span> this<\/span>;<\/span>
\n }<\/span><\/p>\n Stream<\/span><<\/span>T<\/span>><\/span><\/span> build<\/span>(<\/span>)<\/span>;<\/span> \/\/ \u2705 \u5de5\u5382\u65b9\u6cd5：build \u51fa Stream<\/span>
\n }<\/span><\/p>\n \/**
\n * \u2705 \u5de5\u5382\u65b9\u6cd5：\u83b7\u53d6 Builder
\n *\/<\/span>
\n static<\/span> <<\/span>T<\/span>><\/span><\/span> Builder<\/span><<\/span>T<\/span>><\/span><\/span> builder<\/span>(<\/span>)<\/span> {<\/span>
\n return<\/span> new<\/span> Streams.<\/span>StreamBuilderImpl<\/span><<\/span>><\/span><\/span>(<\/span>)<\/span>;<\/span>
\n }<\/span>
\n}<\/span><\/p>\n\u5b8c\u6574\u4f7f\u7528：<\/p>\n \/**
\n * \u2705 \u94fe\u5f0f\u6784\u5efa Stream
\n *\/<\/span>
\nStream<\/span><<\/span>String<\/span>><\/span><\/span> stream =<\/span> Stream<\/span>.<\/span><<\/span>String<\/span>><\/span><\/span>builder<\/span>(<\/span>)<\/span>
\n .<\/span>add<\/span>(<\/span>"Hello"<\/span>)<\/span>
\n .<\/span>add<\/span>(<\/span> |