3招解决ant构建时任务找不到(taskdef cann\'t be found)的问题

    在用ant编译项目时，有时会碰到build.xml中所定义的任务找不到的问题：

点击(此处)折叠或打开

1. [root@tivu25 test]# ant -f build.xml local_war
   
2. Buildfile: build.xml
   
3. 
   
4. local_war:
   
5. 
   
6. BUILD FAILED
   
7. /home/haoqf/software/APM/test/build.xml:18: taskdef class com.ibm.team.build.ant.task.LogPublisherTask cannot be found
   
8. 
   
9. Total time: 0 seconds

这是因为ant在当前java的classpath中找不到类LogPublisherTask（LogPublisherTask由 org.apache.tools.ant.Task派生而来），这时候需要重新指定当前的classpath，让它包含LogPublisherTask所属jar库或者class的路径。有三种方法：
1. 在ant命令行指定：

点击(此处)折叠或打开

1. [root@tivu25 test]# ant -f build.xml local_war -lib /home/haoqf/software/RTC/RTC-BuildSystem-Toolkit-Linux-3.0iFix1/jazz/buildsystem/buildtoolkit/

2. 在build.xml指定：

点击(此处)折叠或打开

1. <?xml version="1.0" encoding="UTF-8"?>
   
2. 
   
3. <project name="BVT_CVT" default="local_war">
   
4.     
   
5.      <target name="local_war">
   
6.         <taskdef name="logPublisher" classname="com.ibm.team.build.ant.task.LogPublisherTask">
   
7.         <classpath>
   
8.             <pathelement location="/home/haoqf/software/RTC/RTC-BuildSystem-Toolkit-Linux-3.0iFix1/jazz/buildsystem/buildtoolkit/"/>
   
9.             <fileset dir="/home/haoqf/software/RTC/RTC-BuildSystem-Toolkit-Linux-3.0iFix1/jazz/buildsystem/buildtoolkit/">
   
10.                 <include name="**/*.jar"/>
    
11.             </fileset>
    
12.         </classpath>
    
13.         </taskdef>
    
14.     
    
15.         <logPublisher repositoryAddress="${repositoryAddress}"    />
    
16. 
    
17.      </target>
    
18. </project>

3. 设定当前环境变量CLASSPATH：

点击(此处)折叠或打开

1. [root@tivu25 test]# export CLASSPATH=$CLASSPATH:/home/haoqf/software/RTC/RTC-BuildSystem-Toolkit-Linux-3.0iFix1/jazz/buildsystem/buildtoolkit/com.ibm.team.build.toolkit_2.2.0.v20110308_0258.jar

其中com.ibm.team.build.toolkit_2.2.0.v20110308_0258.jar包含了类LogPublisherTask的实现。