{"id":1597,"date":"2020-11-20T11:39:48","date_gmt":"2020-11-20T03:39:48","guid":{"rendered":"https:\/\/www.yusian.com\/blog\/?p=1597"},"modified":"2020-11-26T20:46:19","modified_gmt":"2020-11-26T12:46:19","slug":"%e6%b3%a8%e8%a7%a3%e3%80%81%e5%8f%8d%e5%b0%84%e3%80%81%e6%96%87%e4%bb%b6io%e6%b5%81%e7%9a%84%e7%bb%bc%e5%90%88%e5%ba%94%e7%94%a8","status":"publish","type":"post","link":"https:\/\/www.yusian.com\/blog\/java\/2020\/11\/20\/1139481597.html","title":{"rendered":"\u6ce8\u89e3\u3001\u53cd\u5c04\u3001\u6587\u4ef6IO\u6d41\u7684\u7efc\u5408\u5e94\u7528"},"content":{"rendered":"<ul>\n<li>\u51c6\u5907\u4e00\u4e2a\u7b80\u5355\u7684\u6ce8\u89e3\n<pre><code class=\"language-java line-numbers\">package com.yusian.annotation;\n\nimport java.lang.annotation.ElementType;\nimport java.lang.annotation.Retention;\nimport java.lang.annotation.RetentionPolicy;\nimport java.lang.annotation.Target;\n\n\/**\n* \u521b\u5efa\u4e00\u4e2a\u7b80\u5355\u7684\u6ce8\u89e3SACheck\n* \u8be5\u6ce8\u89e3\u53ea\u80fd\u5e94\u7528\u5728\u65b9\u6cd5\u4e0a\n* \u6ce8\u89e3\u4fdd\u7559\u5230\u8fd0\u884c\u65f6\n* \u6ca1\u6709\u5c5e\u6027\uff0c\u53ea\u505a\u6807\u8bb0\u7528\n*\/\n@Target(ElementType.METHOD)\n@Retention(RetentionPolicy.RUNTIME)\npublic @interface SACheck {\n}\n<\/code><\/pre>\n<\/li>\n<li>\u51c6\u5907\u4e00\u4e2a\u7b80\u5355\u7684\u6d4b\u8bd5\u7c7b\n<pre><code class=\"language-java line-numbers\">package com.yusian.annotation;\n\nimport org.junit.Assert;\n\n\/**\n* \u8ba1\u7b97\u5668\u7c7b\uff0c\u51e0\u4e2a\u7b80\u5355\u7684\u65b9\u6cd5\u505a\u6f14\u793a\n*\/\npublic class Calculator {\n\n  @SACheck\n  public void add() {\n      int ret = add(1, 2);\n      String str = null;\n      str.toLowerCase();  \/\/ \u4eba\u4e3a\u5236\u9020bug\uff0c\u68c0\u6d4b\u6d4b\u8bd5\u6548\u679c\n      Assert.assertEquals(3, ret);\n  }\n\n  @SACheck\n  public void sub() {\n      int ret = sub(2, 1);\n      ret = 1 \/ 0;    \/\/ \u4eba\u4e3a\u5236\u9020bug\uff0c\u68c0\u6d4b\u6d4b\u8bd5\u6548\u679c\n      Assert.assertEquals(1, ret);\n  }\n\n  @SACheck\n  public void multiply() {\n      int ret = multiply(2, 3);\n      \/\/ \u4eba\u4e3a\u5236\u9020bug\uff0c\u68c0\u6d4b\u6d4b\u8bd5\u6548\u679c\n      Assert.assertEquals(5, ret);\n  }\n\n  public void show() {\n      System.out.println(\"show...\");\n  }\n\n  public int add(int a, int b) {\n      return a + b;\n  }\n\n  public int sub(int a, int b) {\n      return a - b;\n  }\n\n  public int multiply(int a, int b) {\n      return a * b;\n  }\n\n  public int divide(int a, int b) {\n      return a \/ b;\n  }\n}\n<\/code><\/pre>\n<\/li>\n<li>\u901a\u8fc7\u53cd\u5c04\u673a\u5236\u53ca\u6ce8\u89e3\u7684\u6807\u8bb0\u6d4b\u8bd5\u5e26SACheck\u6ce8\u89e3\u7684\u65b9\u6cd5\uff0c\u5c06\u6d4b\u8bd5\u7ed3\u679c\u5199\u5165\u672c\u5730\u6587\u4ef6\n<pre><code class=\"language-java line-numbers\">package com.yusian.annotation;\n\nimport java.io.*;\nimport java.lang.reflect.Method;\nimport java.util.Arrays;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class AnnoDemo {\n  public static void main(String[] args) throws IOException{\n      \/\/ \u901a\u8fc7Calculator\u7c7b\u5bf9\u8c61\u83b7\u53d6\u6240\u6709\u7684\u6210\u5458\u65b9\u6cd5\n      Calculator c = new Calculator();\n      Method[] declaredMethods = c.getClass().getDeclaredMethods();\n\n      \/\/ bug\u8ba1\u6570\uff0c\u8fd9\u91cc\u672c\u6765\u53ef\u4ee5\u5b9a\u4e49\u4e00\u4e2aint\u53d8\u91cf\u7136\u540e++\u5c31\u884c\u4e86\uff0c\u4f46Lambda\u8868\u8fbe\u5f0f\u4e2d\u4e0d\u652f\u6301\u4fee\u6539\u5916\u90e8\u53d8\u91cf\n      AtomicInteger errNum = new AtomicInteger();\n      \/\/ \u51c6\u5907\u4e00\u4e2aIO\u5199\u5165\u6d41\uff0c\u68c0\u6d4b\u51fa\u6765\u7684bug\u5199\u5165\u5230\u6587\u4ef6\u4e2d\n      BufferedWriter bw = new BufferedWriter(new FileWriter(\"bug.txt\"));\n      \/\/ \u4f7f\u7528\u6d41\u8fdb\u884c\u7b5b\u9009\u4e0e\u904d\u5386\uff0c\u5c06\u5e26\u6709@SACheck\u6ce8\u89e3\u7684\u65b9\u6cd5\u6267\u884c\u5e76\u68c0\u6d4b\u51fa\u662f\u5426\u5f02\u5e38\uff0c\u5982\u679c\u6709\u5219\u5199\u5165\u5230\u6587\u4ef6\n      Arrays.stream(declaredMethods).filter(method -&gt; {\n          return method.getAnnotation(SACheck.class) != null;\n      }).forEach(method -&gt; {\n          try {\n              method.invoke(c);\n          } catch (Exception e) {\n              try {\n                  bw.write(\"\u9519\u8bef\u7c7b\u578b\uff1a\" + e.getCause().getClass().getSimpleName());\n                  bw.newLine();\n                  bw.write(\"\u9519\u8bef\u539f\u56e0\uff1a\" + e.getCause().getMessage());\n                  bw.newLine();\n                  bw.write(\"-------------------\");\n                  bw.newLine();\n                  errNum.getAndIncrement();\n              } catch (IOException ioException) {\n                  ioException.printStackTrace();\n              }\n          }\n      });\n      bw.write(\"\u5171\u68c0\u6d4b\u51fa\" + errNum + \"\u4e2abug\");\n      bw.newLine();\n      bw.flush();\n      bw.close();\n  }\n}\n<\/code><\/pre>\n<\/li>\n<li><strong>\u8f93\u51fa\u6587\u4ef6\uff1abug.txt<\/strong>\n<pre><code class=\"language-cmd line-numbers\">\u9519\u8bef\u7c7b\u578b\uff1aNullPointerException\n\u9519\u8bef\u539f\u56e0\uff1anull\n-\n\u9519\u8bef\u7c7b\u578b\uff1aAssertionError\n\u9519\u8bef\u539f\u56e0\uff1aexpected:&lt;5&gt; but was:&lt;6&gt;\n-\n\u9519\u8bef\u7c7b\u578b\uff1aArithmeticException\n\u9519\u8bef\u539f\u56e0\uff1a\/ by zero\n-\n\u5171\u68c0\u6d4b\u51fa3\u4e2abug\n<\/code><\/pre>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>\u51c6\u5907\u4e00\u4e2a\u7b80\u5355\u7684\u6ce8\u89e3 package com.yusian.annotation; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; \/** * \u521b\u5efa\u4e00\u4e2a\u7b80\u5355\u7684\u6ce8\u89e3SACheck * \u8be5\u6ce8\u89e3\u53ea\u80fd\u5e94\u7528\u5728\u65b9\u6cd5\u4e0a * \u6ce8\u89e3\u4fdd\u7559\u5230\u8fd0\u884c\u65f6 * \u6ca1\u6709\u5c5e\u6027\uff0c\u53ea\u505a\u6807\u8bb0\u7528 *\/ @Target(ElementType.METHOD) @Retention(RetentionPolicy.RUNTIME) public @interface SACheck { } \u51c6\u5907\u4e00\u4e2a\u7b80\u5355\u7684\u6d4b\u8bd5\u7c7b package com.yusian.annotation; import org.junit.Assert; \/** * \u8ba1\u7b97\u5668\u7c7b\uff0c\u51e0\u4e2a\u7b80\u5355\u7684\u65b9\u6cd5\u505a\u6f14\u793a *\/ public class Calculator { @SACheck public void add() { int ret = add(1, 2); String str = null; [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[256,280,281],"class_list":["post-1597","post","type-post","status-publish","format-standard","hentry","category-java","tag-io","tag-280","tag-281"],"_links":{"self":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/posts\/1597","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/comments?post=1597"}],"version-history":[{"count":0,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/posts\/1597\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/media?parent=1597"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/categories?post=1597"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/tags?post=1597"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}