{"id":2819,"date":"2023-04-27T14:04:03","date_gmt":"2023-04-27T06:04:03","guid":{"rendered":"https:\/\/hsin-life.com\/?p=2819"},"modified":"2023-04-27T14:04:03","modified_gmt":"2023-04-27T06:04:03","slug":"java-%e5%ad%97%e4%b8%b2%e9%80%a3%e6%8e%a5%ef%bc%9a%e6%ad%a3%e7%a2%ba%e4%bd%bf%e7%94%a8-string-%e8%88%87-stringbuilder","status":"publish","type":"post","link":"https:\/\/hsin-life.com\/archives\/2819","title":{"rendered":"Java \u5b57\u4e32\u9023\u63a5\uff1a\u6b63\u78ba\u4f7f\u7528 String \u8207 StringBuilder"},"content":{"rendered":"\n<p>\u5728 Java \u4e2d\uff0c\u5b57\u4e32\u9023\u63a5\u662f\u4e00\u500b\u5e38\u898b\u7684\u64cd\u4f5c\u3002<\/p>\n\n\n\n<p>\u8a31\u591a\u958b\u767c\u8005\u53ef\u80fd\u6703\u807d\u8aaa\u904e\uff0c\u7531\u65bc Java \u6c92\u6709\u63d0\u4f9b\u4fee\u6539\u5b57\u4e32\u5167\u5bb9\u7684\u65b9\u6cd5\uff0c\u6240\u4ee5\u5728\u5b57\u4e32\u9023\u63a5\u904e\u7a0b\u4e2d\u53ef\u80fd\u6703\u7522\u751f\u5f88\u591a\u5b57\u4e32\uff0c\u5f9e\u800c\u6d88\u8017\u5927\u91cf\u7cfb\u7d71\u8cc7\u6e90\u3002<\/p>\n\n\n\n<p>\u8981\u6539\u5584\u9019\u500b\u554f\u984c\uff0c\u53ef\u4ee5\u4f7f\u7528 StringBuilder\uff08\u82e5\u9700\u8981\u8003\u616e Thread-Safe \u5247\u4f7f\u7528 StringBuffer\uff09\u3002<\/p>\n\n\n\n<p>\u7136\u800c\uff0c\u4e8b\u5be6\u4e0a Java \u5728\u9032\u884c\u5b57\u4e32\u9023\u63a5\u6642\uff0c\u6703\u81ea\u52d5\u4f7f\u7528 StringBuilder \u9032\u884c\u8655\u7406\u3002<\/p>\n\n\n\n<p>\u4f8b\u5982\uff0c\u7576\u4f60\u4f7f\u7528\u4ee5\u4e0b\u8a9e\u6cd5\u9032\u884c\u9023\u63a5\u6642\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>String s = x + y + z;\r<\/code><\/pre>\n\n\n\n<p>\u5be6\u969b\u4e0a Java \u6703\u5c07\u5176\u8f49\u63db\u70ba\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>String s = new StringBuilder(x).append(y).append(z).toString();\r<\/code><\/pre>\n\n\n\n<p>\u6240\u4ee5\uff0c\u6211\u5011\u4e0d\u9700\u8981\u984d\u5916\u4f7f\u7528 StringBuilder \u4f86\u9032\u884c\u9023\u63a5\u3002<\/p>\n\n\n\n<p>\u4f46\u662f\uff0c\u9019\u4e26\u4e0d\u610f\u5473\u8457\u6211\u5011\u53ef\u4ee5\u5b8c\u5168\u4e0d\u4f7f\u7528 StringBuilder\u3002<\/p>\n\n\n\n<p>\u5728 Java \u81ea\u52d5\u4f7f\u7528 StringBuilder \u9032\u884c\u8655\u7406\u6642\uff0c\u5b83\u662f\u4ee5\u4e00\u500b\u6307\u4ee4\u70ba\u55ae\u4f4d\u7684\u3002<\/p>\n\n\n\n<p>\u4f8b\u5982\uff0c\u4ee5\u4e0b\u4ee3\u78bc\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>String s = x;\r\ns += y;\r\ns += z;\r<\/code><\/pre>\n\n\n\n<p>\u9019\u6a23\u7684\u5beb\u6cd5\u6703\u7522\u751f\u4e09\u500b StringBuilder\uff0c\u4e26\u57f7\u884c\u4e09\u6b21 toString()\uff0c\u53cd\u800c\u589e\u52a0\u4e86\u7cfb\u7d71\u8cc7\u6e90\u7684\u6d88\u8017\u3002<\/p>\n\n\n\n<p>\u540c\u6a23\u7684\uff0c\u4e0b\u9762\u7684\u4ee3\u78bc\u7247\u6bb5\u4e5f\u6709\u985e\u4f3c\u554f\u984c\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>String s = \"\";\r\nfor (String x : someStringCollection) {\r\n    s += x;\r\n}\r<\/code><\/pre>\n\n\n\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6bcf\u6b21\u5faa\u74b0\u90fd\u6703\u7522\u751f\u4e00\u500b StringBuilder \u4e26\u57f7\u884c\u4e00\u6b21 toString()\uff0c\u5c0e\u81f4\u7cfb\u7d71\u8cc7\u6e90\u7684\u6d6a\u8cbb\u3002<\/p>\n\n\n\n<p>\u56e0\u6b64\uff0c\u6b63\u78ba\u7684\u505a\u6cd5\u662f\u5728\u9700\u8981\u9032\u884c\u591a\u6b21\u5b57\u4e32\u9023\u63a5\u64cd\u4f5c\u6642\uff0c\u4f7f\u7528 StringBuilder\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>StringBuilder sb = new StringBuilder();\r\nfor (String x : someStringCollection) {\r\n    sb.append(x);\r\n}\r\nString s = sb.toString();\r<\/code><\/pre>\n\n\n\n<p>\u9019\u6a23\u53ef\u4ee5\u6709\u6548\u6e1b\u5c11\u7cfb\u7d71\u8cc7\u6e90\u7684\u6d88\u8017\u3002<\/p>\n\n\n\n<p>\u7e3d\u7d50\u8d77\u4f86\uff0c\u6211\u5011\u61c9\u8a72\u5728 Java \u7a0b\u5f0f\u4e2d\u6839\u64da\u5177\u9ad4\u9700\u6c42\uff0c\u9069\u6642\u9078\u64c7\u4f7f\u7528 String \u6216 StringBuilder \u9032\u884c\u5b57\u4e32\u9023\u63a5\uff0c\u4ee5\u9054\u5230\u6700\u4f73\u7684\u6548\u80fd\u548c\u8cc7\u6e90\u5229\u7528\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u672c\u6587\u5c07\u4ecb\u7d39 Java \u4e2d String \u548c StringBuilder \u7684\u6b63\u78ba\u4f7f\u7528\u65b9\u5f0f\uff0c\u4ee5\u53ca\u4e0d\u7576\u4f7f\u7528\u6642\u53ef\u80fd\u9020\u6210\u7684\u7cfb\u7d71\u8cc7\u6e90\u6d88\u8017\u554f\u984c\u3002<\/p>\n","protected":false},"author":1,"featured_media":2820,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[145],"tags":[87,619,712,711,713,714],"aioseo_notices":[],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/i0.wp.com\/hsin-life.com\/wp-content\/uploads\/2023\/04\/pexels-photo-574071-1.jpeg?fit=1880%2C1245&ssl=1","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/posts\/2819"}],"collection":[{"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/comments?post=2819"}],"version-history":[{"count":0,"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/posts\/2819\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/media\/2820"}],"wp:attachment":[{"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/media?parent=2819"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/categories?post=2819"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hsin-life.com\/wp-json\/wp\/v2\/tags?post=2819"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}