这是ant源码
<?xml version="1.0" encoding="UTF-8"?>
description
<!-- =================================
target: BuildAllHeaders
================================= -->
<target name="BuildAllHeaders" >
<antcall target="BuildGetStringHeader"></antcall>
<antcall target="BuildGetIntHeader"></antcall>
</target>
<!-- - - - - - - - - - - - - - - - - -
target: depends
- - - - - - - - - - - - - - - - - -->
<target name="BuildGetStringHeader">
<javah destdir="./jni" classpath="./bin/classes/" class="com.longertek.hellondk.GetString"></javah>
</target>
<!-- - - - - - - - - - - - - - - - - -
target: BuildGetIntHeader
- - - - - - - - - - - - - - - - - -->
<target name="BuildGetIntHeader">
</target>
双击ant出现如下错误
Buildfile: E:\workspace\Android\HelloNDK\builder_headers.xml
BuildAllHeaders:
BuildGetStringHeader:
[javah] Exception in thread "main" java.lang.NullPointerException
[javah] at com.sun.tools.javah.JavahTask.run(JavahTask.java:503)
[javah] at com.sun.tools.javah.JavahTask.run(JavahTask.java:329)
[javah] at com.sun.tools.javah.Main.main(Main.java:46)
BUILD FAILED
E:\workspace\Android\HelloNDK\builder_headers.xml:19: The following error occurred while executing this line:
E:\workspace\Android\HelloNDK\builder_headers.xml:27: compilation failed
Total time: 880 milliseconds
这个错误是什么原因呢