用浏览器来查看Tomcat的运行状态：
配置Tomcat的管理用户和权限。
打开%Tomcat_Home%/conf/目录下的tomcat-user.xml文件，配置以下内容：
1<role rolename="manager-status"/> 2<role rolename="manager"/> 3<role rolename="manager-jmx"/> 4<role rolename="manager-gui"/> 5<role rolename="manager-script"/> 6<role rolename="admin"/> 7 8<user username="tomcat" password="tomcat" roles="tomcat"/> 9 10<user username="admin" password="tomcat" roles="manager,manager-gui,admin,manager-status,manager-jmx,manager-script"/>
此时可通过admin用户来访问tomcat的状态，在浏览器地址中输入：
http://localhost:8080/manager/status?XML=true
输入用户名：admin,密码：tomcat. 出现以下页面，即Tomcat的运行状态。
或者可以直接访问：
http://admin:tomcat[@localhost](http://my.oschina.net/u/570656) :8080/manager/status?XML=true
Java程序获取Tomcat运行状态：
根据上面的思路，可以通过URL来获取Tomcat manager返回的信息，再解析这个信息就可以了，参考cacti的监控方式中，用perl编写的监控模板也是如此，如下：
1 my $host = shift; 2 my $username = shift; 3 my $password = shift; 4 my $connector = shift or &usage; 5 my $url = "http://$username:$password"."\@$host/manager/status?XML=true"; 6 7 my $xml = `GET $url`; 8 9 my $status = XMLin($xml);
因此Java也可参考此方法：
1@Test 2 public void test1() throws IOException { 3 URL url = null; 4 InputStream is = null; 5 StringBuffer resultBuffer = new StringBuffer(); 6 BufferedReader breader = null; 7 try { 8 url = new URL( 9 "http://admin:tomcat@localhost:8080/manager/status?XML=true"); 10 HttpURLConnection conn = (HttpURLConnection) url.openConnection(); 11 is = conn.getInputStream(); 12 13 breader = new BufferedReader(new InputStreamReader(is)); 14 String line = ""; 15 while ((line = breader.readLine()) != null) { 16 resultBuffer.append(line); 17 } 18 } catch (MalformedURLException e) { 19 e.printStackTrace(); 20 } finally { 21 if (breader != null) 22 breader.close(); 23 if (is != null) 24 is.close(); 25 } 26 System.out.println(resultBuffer.toString()); 27 }
运行时出现如下错误：
1java.io.IOException: Server returned HTTP response code: 401 for URL: http://admin:tomcat@localhost:8080/manager/status?XML=true 2 at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1625) 3 at com.merit.monitor.tomcat.TestTomcatStatus.test1(TestTomcatStatus.java:57) 4 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 5 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 6 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 7 at java.lang.reflect.Method.invoke(Method.java:606) 8 at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44) 9 at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15) 10 at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41) 11 at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20) 12 at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79) 13 at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71) 14 at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49) 15 at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193) 16 at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52) 17 at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191) 18 at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42) 19 at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184) 20 at org.junit.runners.ParentRunner.run(ParentRunner.java:236) 21 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) 22 at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) 23 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467) 24 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683) 25 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390) 26 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
出错原因可以去stackoverview上查看，这里直接给出正确的解决方法：
1、编写获取Tomcat状态的字符串方法：
1/** 2 * @Description: 获取指定URL的内容 3 * @Version1.0 2014-7-23 下午02:18:22 by xuqiang（xuqiang@merit.com）创建 4 * @param tempurl url地址 5 * @param username tomcat 管理用户名 6 * @param password tomcat 管理用户密码 7 * @return 8 * @throws IOException 9 */ 10 public static String getHtmlContext(String tempurl, String username, String password) throws IOException { 11 URL url = null; 12 BufferedReader breader = null; 13 InputStream is = null; 14 StringBuffer resultBuffer = new StringBuffer(); 15 try { 16 url = new URL(tempurl); 17 String userPassword = username + ":" + password; 18 String encoding = new sun.misc.BASE64Encoder().encode (userPassword.getBytes());//在classpath中添加rt.jar包，在%java_home%/jre/lib/rt.jar 19 20 HttpURLConnection conn = (HttpURLConnection) url.openConnection(); 21 conn.setRequestProperty("Authorization", "Basic " + encoding); 22 is = conn.getInputStream(); 23 breader = new BufferedReader(new InputStreamReader(is)); 24 String line = ""; 25 while ((line = breader.readLine()) != null) { 26 resultBuffer.append(line); 27 } 28 } catch (MalformedURLException e) { 29 e.printStackTrace(); 30 } finally { 31 if(breader != null) 32 breader.close(); 33 if(is != null) 34 is.close(); 35 } 36 return resultBuffer.toString(); 37 }
2、编写测试方法：
1@Test 2 public void test() { 3 String result = ""; 4 Document document = null;//引入org.dom4j包 5 try { 6 result = GetHtmlContext.getHtmlContext("http://localhost:8080/manager/status?XML=true", "admin", "tomcat"); 7 document = DocumentHelper.parseText(result);//将字符串转化为XML的Document 8 } catch (IOException e) { 9 e.printStackTrace(); 10 } catch (DocumentException e) { 11 e.printStackTrace(); 12 } 13 System.out.println(document.asXML()); 14 }
运行junit,正常打印监控状态的XML格式内容。这样就可以解析XML Dom的值获取Tomcat的运行状态。