Unable to locate tools.jar. Expected to find it in C:/Program Files/Java/jre

Unable to locate tools.jar. Expected to find it in C:/Program Files/Java/jre 
命令行敲ant命令后提示：“Unable to locate tools.jar. Expected to find it in C:/Program Files/Java/jre6/li”；ANT_HOME环境变量已经配置； 

解决途径：将“C:/Program Files/Java/jdk1.6.0_16/lib”目录下的tools.jar文件拷贝到“C:/Program Files/Java/jre6/lib”目录下，重新运行命令ant，运行正常，问题解决。