“`”<\/p>\n
<h3>\u8ba4\u8bc6\u7ebf\u7a0b\u6b7b\u9501<\/h3><\/p>\n
\u591a\u4e2a\u7ebf\u7a0b\u540c\u65f6\u88ab\u963b\u585e\uff0c\u5b83\u4eec\u4e2d\u7684\u4e00\u4e2a\u6216\u8005\u5168\u90e8\u90fd\u5728\u7b49\u5f85\u67d0\u4e2a\u8d44\u6e90\u88ab\u91ca\u653e\u3002\u7531\u4e8e\u7ebf\u7a0b\u88ab\u65e0\u9650\u671f\u5730\u963b\u585e\uff0c\u56e0\u6b64\u7a0b\u5e8f\u4e0d\u53ef\u80fd\u6b63\u5e38\u7ec8\u6b62\u3002<\/p>\n
\u5982\u4e0b\u56fe\u6240\u793a\uff0c\u7ebf\u7a0b A \u6301\u6709\u8d44\u6e90 2\uff0c\u7ebf\u7a0b B \u6301\u6709\u8d44\u6e90 1\uff0c\u4ed6\u4eec\u540c\u65f6\u90fd\u60f3\u7533\u8bf7\u5bf9\u65b9\u7684\u8d44\u6e90\uff0c\u6240\u4ee5\u8fd9\u4e24\u4e2a\u7ebf\u7a0b\u5c31\u4f1a\u4e92\u76f8\u7b49\u5f85\u800c\u8fdb\u5165\u6b7b\u9501\u72b6\u6001\u3002<\/p>\n
<img src=""https:\/\/my-blog-to-use.oss-cn-beijing.aliyuncs.com\/2019-4\/2019-4%E6%AD%BB%E9%94%811.png"" referrerpolicy=""no-referrer"" alt=""\u7ebf\u7a0b\u6b7b\u9501\u793a\u610f\u56fe "" style=""width: 100%;""><\/p>\n
\u4e0b\u9762\u901a\u8fc7\u4e00\u4e2a\u4f8b\u5b50\u6765\u8bf4\u660e\u7ebf\u7a0b\u6b7b\u9501,\u4ee3\u7801\u6a21\u62df\u4e86\u4e0a\u56fe\u7684\u6b7b\u9501\u7684\u60c5\u51b5 (\u4ee3\u7801\u6765\u6e90\u4e8e\u300a\u5e76\u53d1\u7f16\u7a0b\u4e4b\u7f8e\u300b)\uff1a<\/p><\/p>\n
<pre><code>public class DeadLockDemo { private static Object resource1 = new Object();\/\/\u8d44\u6e90 1 private static Object resource2 = new Object();\/\/\u8d44\u6e90 2 public static void main(String[] args) { new Thread(() -> { synchronized (resource1) { System.out.println(Thread.currentThread() + ""get resource1""); try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println(Thread.currentThread() + ""waiting get resource2""); synchronized (resource2) { System.out.println(Thread.currentThread() + ""get resource2""); } } }, ""\u7ebf\u7a0b 1"").start(); new Thread(() -> { synchronized (resource2) { System.out.println(Thread.currentThread() + ""get resource2""); try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println(Thread.currentThread() + ""waiting get resource1""); synchronized (resource1) { System.out.println(Thread.currentThread() + ""get resource1""); } } }, ""\u7ebf\u7a0b 2"").start(); }}<\/code><\/pre><\/p>\n
Output<\/p>\n
<pre><code>Thread[\u7ebf\u7a0b 1,5,main]get resource1Thread[\u7ebf\u7a0b 2,5,main]get resource2Thread[\u7ebf\u7a0b 1,5,main]waiting get resource2Thread[\u7ebf\u7a0b 2,5,main]waiting get resource1<\/code><\/pre><\/p>\n
\u7ebf\u7a0b A \u901a\u8fc7 synchronized (resource1) \u83b7\u5f97 resource1 \u7684\u76d1\u89c6\u5668\u9501\uff0c\u7136\u540e\u901a\u8fc7<code>Thread.sleep(1000)<span style=""font-family:"Open Sans", "Clear Sans", "Helvetica Neue", Helvetica, Arial, sans-serif"">;<\/span><\/code>\u8ba9\u7ebf\u7a0b A \u4f11\u7720 1s \u4e3a\u7684\u662f\u8ba9\u7ebf\u7a0b B \u5f97\u5230\u6267\u884c\u7136\u540e\u83b7\u53d6\u5230 resource2 \u7684\u76d1\u89c6\u5668\u9501\u3002\u7ebf\u7a0b A \u548c\u7ebf\u7a0b B \u4f11\u7720\u7ed3\u675f\u4e86\u90fd\u5f00\u59cb\u4f01\u56fe\u8bf7\u6c42\u83b7\u53d6\u5bf9\u65b9\u7684\u8d44\u6e90\uff0c\u7136\u540e\u8fd9\u4e24\u4e2a\u7ebf\u7a0b\u5c31\u4f1a\u9677\u5165\u4e92\u76f8\u7b49\u5f85\u7684\u72b6\u6001\uff0c\u8fd9\u4e5f\u5c31\u4ea7\u751f\u4e86\u6b7b\u9501\u3002\u4e0a\u9762\u7684\u4f8b\u5b50\u7b26\u5408\u4ea7\u751f\u6b7b\u9501\u7684\u56db\u4e2a\u5fc5\u8981\u6761\u4ef6\u3002<\/p>\n
\u5b66\u8fc7\u64cd\u4f5c\u7cfb\u7edf\u7684\u670b\u53cb\u90fd\u77e5\u9053\u4ea7\u751f\u6b7b\u9501\u5fc5\u987b\u5177\u5907\u4ee5\u4e0b\u56db\u4e2a\u6761\u4ef6\uff1a<\/p>\n
<ol><li>\u4e92\u65a5\u6761\u4ef6\uff1a\u8be5\u8d44\u6e90\u4efb\u610f\u4e00\u4e2a\u65f6\u523b\u53ea\u7531\u4e00\u4e2a\u7ebf\u7a0b\u5360\u7528\u3002<\/li><li>\u8bf7\u6c42\u4e0e\u4fdd\u6301\u6761\u4ef6\uff1a\u4e00\u4e2a\u8fdb\u7a0b\u56e0\u8bf7\u6c42\u8d44\u6e90\u800c\u963b\u585e\u65f6\uff0c\u5bf9\u5df2\u83b7\u5f97\u7684\u8d44\u6e90\u4fdd\u6301\u4e0d\u653e\u3002<\/li><li>\u4e0d\u5265\u593a\u6761\u4ef6:\u7ebf\u7a0b\u5df2\u83b7\u5f97\u7684\u8d44\u6e90\u5728\u672b\u4f7f\u7528\u5b8c\u4e4b\u524d\u4e0d\u80fd\u88ab\u5176\u4ed6\u7ebf\u7a0b\u5f3a\u884c\u5265\u593a\uff0c\u53ea\u6709\u81ea\u5df1\u4f7f\u7528\u5b8c\u6bd5\u540e\u624d\u91ca\u653e\u8d44\u6e90\u3002<\/li><li>\u5faa\u73af\u7b49\u5f85\u6761\u4ef6:\u82e5\u5e72\u8fdb\u7a0b\u4e4b\u95f4\u5f62\u6210\u4e00\u79cd\u5934\u5c3e\u76f8\u63a5\u7684\u5faa\u73af\u7b49\u5f85\u8d44\u6e90\u5173\u7cfb\u3002<\/li><\/ol><\/p>\n
<h3>\u5982\u4f55\u9884\u9632\u7ebf\u7a0b\u6b7b\u9501?<\/h3><\/p>\n
\u6211\u4eec\u53ea\u8981\u7834\u574f\u4ea7\u751f\u6b7b\u9501\u7684\u56db\u4e2a\u6761\u4ef6\u4e2d\u7684\u5176\u4e2d\u4e00\u4e2a\u5c31\u53ef\u4ee5\u4e86\u3002<\/p>\n
<strong>\u7834\u574f\u4e92\u65a5\u6761\u4ef6<\/strong><\/p>\n
\u8fd9\u4e2a\u6761\u4ef6\u6211\u4eec\u6ca1\u6709\u529e\u6cd5\u7834\u574f\uff0c\u56e0\u4e3a\u6211\u4eec\u7528\u9501\u672c\u6765\u5c31\u662f\u60f3\u8ba9\u4ed6\u4eec\u4e92\u65a5\u7684\uff08\u4e34\u754c\u8d44\u6e90\u9700\u8981\u4e92\u65a5\u8bbf\u95ee\uff09\u3002<\/p>\n
<strong>\u7834\u574f\u8bf7\u6c42\u4e0e\u4fdd\u6301\u6761\u4ef6<\/strong><\/p>\n
\u4e00\u6b21\u6027\u7533\u8bf7\u6240\u6709\u7684\u8d44\u6e90\u3002<\/p>\n
<strong>\u7834\u574f\u4e0d\u5265\u593a\u6761\u4ef6<\/strong><\/p>\n
\u5360\u7528\u90e8\u5206\u8d44\u6e90\u7684\u7ebf\u7a0b\u8fdb\u4e00\u6b65\u7533\u8bf7\u5176\u4ed6\u8d44\u6e90\u65f6\uff0c\u5982\u679c\u7533\u8bf7\u4e0d\u5230\uff0c\u53ef\u4ee5\u4e3b\u52a8\u91ca\u653e\u5b83\u5360\u6709\u7684\u8d44\u6e90\u3002<\/p>\n
<strong>\u7834\u574f\u5faa\u73af\u7b49\u5f85\u6761\u4ef6<\/strong><\/p>\n
\u9760\u6309\u5e8f\u7533\u8bf7\u8d44\u6e90\u6765\u9884\u9632\u3002\u6309\u67d0\u4e00\u987a\u5e8f\u7533\u8bf7\u8d44\u6e90\uff0c\u91ca\u653e\u8d44\u6e90\u5219\u53cd\u5e8f\u91ca\u653e\u3002\u7834\u574f\u5faa\u73af\u7b49\u5f85\u6761\u4ef6\u3002<\/p>\n
\u6211\u4eec\u5bf9\u7ebf\u7a0b 2 \u7684\u4ee3\u7801\u4fee\u6539\u6210\u4e0b\u9762\u8fd9\u6837\u5c31\u4e0d\u4f1a\u4ea7\u751f\u6b7b\u9501\u4e86\u3002<\/p>\n
<pre><code> new Thread(() -> { synchronized (resource1) { System.out.println(Thread.currentThread() + ""get resource1""); try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println(Thread.currentThread() + ""waiting get resource2""); synchronized (resource2) { System.out.println(Thread.currentThread() + ""get resource2""); } } }, ""\u7ebf\u7a0b 2"").start();<\/code><\/pre><\/p>\n
Output<\/p>\n
<pre><code>Thread[\u7ebf\u7a0b 1,5,main]get resource1Thread[\u7ebf\u7a0b 1,5,main]waiting get resource2Thread[\u7ebf\u7a0b 1,5,main]get resource2Thread[\u7ebf\u7a0b 2,5,main]get resource1Thread[\u7ebf\u7a0b 2,5,main]waiting get resource2Thread[\u7ebf\u7a0b 2,5,main]get resource2Process finished with exit code 0<\/code><\/pre><\/p>\n
\u6211\u4eec\u5206\u6790\u4e00\u4e0b\u4e0a\u9762\u7684\u4ee3\u7801\u4e3a\u4ec0\u4e48\u907f\u514d\u4e86\u6b7b\u9501\u7684\u53d1\u751f?<\/p>\n
\u7ebf\u7a0b 1 \u9996\u5148\u83b7\u5f97\u5230 resource1 \u7684\u76d1\u89c6\u5668\u9501,\u8fd9\u65f6\u5019\u7ebf\u7a0b 2 \u5c31\u83b7\u53d6\u4e0d\u5230\u4e86\u3002\u7136\u540e\u7ebf\u7a0b 1 \u518d\u53bb\u83b7\u53d6 resource2 \u7684\u76d1\u89c6\u5668\u9501\uff0c\u53ef\u4ee5\u83b7\u53d6\u5230\u3002\u7136\u540e\u7ebf\u7a0b 1 \u91ca\u653e\u4e86\u5bf9 resource1\u3001resource2 \u7684\u76d1\u89c6\u5668\u9501\u7684\u5360\u7528\uff0c\u7ebf\u7a0b 2 \u83b7\u53d6\u5230\u5c31\u53ef\u4ee5\u6267\u884c\u4e86\u3002\u8fd9\u6837\u5c31\u7834\u574f\u4e86\u7834\u574f\u5faa\u73af\u7b49\u5f85\u6761\u4ef6\uff0c\u56e0\u6b64\u907f\u514d\u4e86\u6b7b\u9501\u3002<\/p>\n
<pre><code> "“`
\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
“`” <h3>\u8ba4\u8bc6\u7ebf\u7a0b\u6b7b\u9501<\/h3> \u591a\u4e2a\u7ebf\u7a0b\u540c\u65f6\u88ab\u963b\u585e\uff0c\u5b83 […]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-37521","post","type-post","status-publish","format-standard","hentry","category-c"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/37521","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=37521"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/37521\/revisions"}],"predecessor-version":[{"id":37522,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/37521\/revisions\/37522"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=37521"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=37521"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=37521"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}