maven內置常量

轉載：http://zheng12tian.iteye.com/blog/1770909

Maven內置變量說明： 

• ${basedir} 項目根目錄
• ${project.build.directory} 構建目錄，缺省爲target
• ${project.build.outputDirectory} 構建過程輸出目錄，缺省爲target/classes
• ${project.build.finalName} 產出物名稱，缺省爲${project.artifactId}-${project.version}
• ${project.packaging} 打包類型，缺省爲jar
• ${project.xxx} 當前pom文件的任意節點的內容