Java 线程池：CachedThreadPool、FixedThreadPool、SingleThreadPool 区别及队列特点

Java\u4e2d\u7684\u7ebf\u7a0b\u6c60\u662f\u4e00\u79cd\u7ba1\u7406\u7ebf\u7a0b\u7684\u673a\u5236\uff0c\u53ef\u4ee5\u91cd\u590d\u4f7f\u7528\u7ebf\u7a0b\uff0c\u63d0\u9ad8\u7a0b\u5e8f\u7684\u6548\u7387\u548c\u6027\u80fd\u3002Java\u63d0\u4f9b\u4e86\u4e09\u79cd\u5e38\u89c1\u7684\u7ebf\u7a0b\u6c60\uff1aCachedThreadPool\u3001FixedThreadPool\u548cSingleThreadPool\u3002\n\n1\u3002CachedThreadPool\uff1a\nCachedThreadPool\u662f\u4e00\u79cd\u6839\u636e\u9700\u8981\u81ea\u52a8\u521b\u5efa\u548c\u56de\u6536\u7ebf\u7a0b\u7684\u7ebf\u7a0b\u6c60\u3002\u5f53\u7ebf\u7a0b\u6c60\u4e2d\u7684\u7ebf\u7a0b\u7a7a\u95f4\u8d85\u8fc760\u79d2\u65f6\uff0c\u5c31\u4f1a\u88ab\u56de\u6536\uff0c\u5f53\u4efb\u52a1\u5230\u6765\u65f6\uff0c\u5982\u679c\u7ebf\u7a0b\u6c60\u4e2d\u6709\u7a7a\u95f4\u7ebf\u7a0b\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\uff0c\u5982\u679c\u6ca1\u6709\u7a7a\u95f4\u7ebf\u7a0b\uff0c\u5219\u521b\u5efa\u65b0\u7684\u7ebf\u7a0b\u3002CachedThreadPool\u9002\u5408\u5728\u6267\u884c\u5f88\u591a\u77ed\u671f\u5e7f\u6cdb\u4efb\u52a1\u7684\u573a\u666f\uff0c\u7ebf\u7a0b\u7684\u521b\u5efa\u548c\u7834\u574f\u90fd\u7531\u7ebf\u7a0b\u6c60\u81ea\u52a8\u7ba1\u7406\u3002\n\n\u7684\u5217\u5408\u7279\u70b9\uff1aCachedThreadPool\u4f7f\u7528\u7684\u662fSynchronousQueue\u5217\u5408\uff0c\u5b83\u662f\u4e00\u4e2a\u6ca1\u6709\u5bb9\u91cf\u7684\u5217\u5408\uff0c\u53ea\u80fd\u5305\u542b\u4e00\u4e2a\u5143\u7d20\u3002\u5728CachedThreadPool\u4e2d\uff0c\u4efb\u52a1\u63d0\u4ea4\u5230\u7ebf\u7a0b\u6c60\u540e\uff0c\u5982\u679c\u6ca1\u6709\u7a7a\u95f4\u7ebf\u7a0b\uff0c\u5219\u4f1a\u521b\u5efa\u65b0\u7684\u7ebf\u7a0b\u6765\u6267\u884c\u4efb\u52a1\uff0c\u800c\u4e0d\u4f1a\u5c06\u4efb\u52a1\u6dfb\u52a0\u5230\u5217\u5408\u4e2d\u7b49\u5f85\u3002\n\n2\u3002FixedThreadPool\uff1a\nFixedThreadPool\u662f\u4e00\u4e2a\u56fa\u5b9a\u5927\u5c0f\u7684\u7ebf\u7a0b\u6c60\uff0c\u7ebf\u7a0b\u6c60\u4e2d\u7684\u7ebf\u7a0b\u6570\u91cf\u662f\u56fa\u5b9a\u7684\uff0c\u5f53\u6709\u65b0\u7684\u4efb\u52a1\u63d0\u4ea4\u65f6\uff0c\u5982\u679c\u7ebf\u7a0b\u6c60\u4e2d\u6709\u7a7a\u95f4\u7ebf\u7a0b\uff0c\u5219\u76f4\u63a5\u4f7f\u7528\uff0c\u5982\u679c\u6ca1\u6709\u7a7a\u95f4\u7ebf\u7a0b\uff0c\u5219\u5c06\u4efb\u52a1\u6dfb\u52a0\u5230\u5217\u5408\u4e2d\u7b49\u5f85\u3002FixedThreadPool\u9002\u5408\u5728\u6267\u884c\u957f\u671f\u7684\u4efb\u52a1\uff0c\u9650\u5236\u7ebf\u7a0b\u6570\u91cf\u53ef\u4ee5\u9632\u6b62\u8d44\u6e90\u8017\u7aed\u3002\n\n\u7684\u5217\u5408\u7279\u70b9\uff1aFixedThreadPool\u4f7f\u7528\u7684\u662fLinkedBlockingQueue\u5217\u5408\uff0c\u5b83\u662f\u4e00\u4e2a\u65e0\u754c\u5217\u5408\uff0c\u53ef\u4ee5\u65e0\u9650\u5730\u6dfb\u52a0\u4efb\u52a1\u3002\u5f53\u7ebf\u7a0b\u6c60\u4e2d\u7684\u7ebf\u7a0b\u6570\u91cf\u8fbe\u5230\u6700\u5927\u503c\u65f6\uff0c\u65b0\u7684\u4efb\u52a1\u4f1a\u88ab\u6dfb\u52a0\u5230\u5217\u5408\u4e2d\u7b49\u5f85\u3002\n\n3\u3002SingleThreadPool\uff1a\nSingleThreadPool\u662f\u4e00\u4e2a\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u7684\u7ebf\u7a0b\u6c60\uff0c\u8be5\u7ebf\u7a0b\u6c60\u4e2d\u7684\u7ebf\u7a0b\u6309\u987a\u5e8f\u6267\u884c\u4efb\u52a1\u3002\u5982\u679c\u73b0\u5728\u7ebf\u7a0b\u6b63\u5728\u6267\u884c\u4efb\u52a1\uff0c\u65b0\u7684\u4efb\u52a1\u4f1a\u88ab\u6dfb\u52a0\u5230\u5217\u5408\u4e2d\u7b49\u5f85\uff0c\u76f4\u5230\u73b0\u5728\u7ebf\u7a0b\u6267\u884c\u5b8c\u4efb\u52a1\u540e\u518d\u6267\u884c\u4e0b\u4e00\u4e2a\u4efb\u52a1\u3002\n\n\u7684\u5217\u5408\u7279\u70b9\uff1aSingleThreadPool\u4f7f\u7528\u7684\u662fLinkedBlockingQueue\u5217\u5408\uff0c\u5b83\u662f\u4e00\u4e2a\u65e0\u754c\u5217\u5408\uff0c\u53ef\u4ee5\u65e0\u9650\u5730\u6dfb\u52a0\u4efb\u52a1\u3002\u5f53\u7ebf\u7a0b\u6b63\u5728\u6267\u884c\u4efb\u52a1\u65f6\uff0c\u65b0\u7684\u4efb\u52a1\u4f1a\u88ab\u6dfb\u52a0\u5230\u5217\u5408\u4e2d\u7b49\u5f85\u3002\n\n\u7b5b\u4e0a\u6240\u8ff0\uff0cCachedThreadPool\u9002\u5408\u5728\u6267\u884c\u77ed\u671f\u5e7f\u6cdb\u4efb\u52a1\uff0c\u7ebf\u7a0b\u6570\u91cf\u6839\u636e\u9700\u8981\u52a8\u6001\u8c03\u6574\uff1bFixedThreadPool\u9002\u5408\u5728\u6267\u884c\u957f\u671f\u4efb\u52a1\uff0c\u7ebf\u7a0b\u6570\u91cf\u56fa\u5b9a\uff1bSingleThreadPool\u9002\u5408\u5728\u9700\u8981\u6309\u987a\u5e8f\u6267\u884c\u4efb\u52a1\u7684\u573a\u666f\u3002\u5b89\u5168\u7684\u5217\u5408\u7279\u70b9\u4e5f\u4e0d\u4e00\u6837\uff0cCachedThreadPool\u4f7f\u7528\u7684\u662fSynchronousQueue\u5217\u5408\uff0cFixedThreadPool\u548cSingleThreadPool\u4f7f\u7528\u7684\u662fLinkedBlockingQueue\u5217\u5408\u3002