eclipse ctrl+左击不能关联相应文件

<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
<name>mycompany</name>
<comment></comment>
<projects>
</projects>
<buildSpec>
<buildCommand>
<name>net.sourceforge.phpeclipse.parserbuilder</name>
<arguments>
</arguments>
</buildCommand>
</buildSpec>
<natures>
<nature>net.sourceforge.phpeclipse.phpnature</nature>
</natures>
</projectDescription>