jenkins启动时报错如下：

jenkins配置安装：
1、 http://updates.jenkins-ci.org/download/war/
下载得到jenkins的war包，放到指定目录下。
2、 在控制台到相应的目录，输入java -jar jenkins.war
3、 启动成功，提示finished
4、浏览器中输入：http://localhost:8080，默认端口号
5、如果能出现jenkins的页面，说明启动成功。
6、可以新建自己的项目，一般选择自由风格即可。
7、可以添加执行的时间，添加一些插件，shell脚本执行命令等

java.io.IOException: Failed to start Jetty
        at winstone.Launcher.<init>(Launcher.java:186)
        at winstone.Launcher.main(Launcher.java:354)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.lang.reflect.Method.invoke(Unknown Source)
        at Main._main(Main.java:344)
        at Main.main(Main.java:160)
Caused by: java.net.BindException: Address already in use: bind
        at sun.nio.ch.Net.bind0(Native Method)
        at sun.nio.ch.Net.bind(Unknown Source)
        at sun.nio.ch.Net.bind(Unknown Source)
        at sun.nio.ch.ServerSocketChannelImpl.bind(Unknown Source)
        at sun.nio.ch.ServerSocketAdaptor.bind(Unknown Source)
        at org.eclipse.jetty.server.ServerConnector.openAcceptChannel(ServerConnector.java:339)
        at org.eclipse.jetty.server.ServerConnector.open(ServerConnector.java:307)
        at org.eclipse.jetty.server.AbstractNetworkConnector.doStart(AbstractNetworkConnector.java:80)
        at org.eclipse.jetty.server.ServerConnector.doStart(ServerConnector.java:235)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
        at org.eclipse.jetty.server.Server.doStart(Server.java:395)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
        at winstone.Launcher.<init>(Launcher.java:184)
        ... 7 more

解决方法：修改Jenkins端口java -jar jenkins.war --httpPort=9876
启动成功： http://localhost:9876
Jenkins initial setup is required. An admin user has been created and a password generated.
Please use the following password to proceed to installation:

323b9eb75be3474ab9db05cb9a3b74d3

新改的用户名和密码都是admin