测试文件：hello-jni/src/com/example/hellojni/HelloJni.java

/**

* 该文件来自 Android NDK Sample - HelloJni， 为了便于说明问题，我作了一些修改。

*/

package com.example.hellojni;

public class HelloJni

{

public native String stringFromJNI();

public native String unimplementedStringFromJNI();

static {

System.loadLibrary("hello-jni");

}

}

错误一

david@xmomx:hellojni$ javac HelloJni.java

david@xmomx:hellojni$ ls

Hello.class Hello.h Hello.java HelloJni.class HelloJni.java

david@xmomx:hellojni$ javah -jni HelloJni

error: cannot access HelloJni

bad class file: ./HelloJni.class

class file contains wrong class: com.example.hellojni.HelloJni

Please remove or make sure it appears in the correct subdirectory of the classpath.

com.sun.tools.javac.util.Abort

at com.sun.tools.javac.comp.Check.completionError(Check.java:164)

at com.sun.tools.javadoc.DocEnv.loadClass(DocEnv.java:149)

at com.sun.tools.javadoc.RootDocImpl.(RootDocImpl.java:77)

at com.sun.tools.javadoc.JavadocTool.getRootDocImpl(JavadocTool.java:159)

at com.sun.tools.javadoc.Start.parseAndExecute(Start.java:330)

at com.sun.tools.javadoc.Start.begin(Start.java:128)

at com.sun.tools.javadoc.Main.execute(Main.java:66)

at com.sun.tools.javah.Main.main(Main.java:147)

javadoc: error - fatal error

2 errors

错误原因，没有在正确的路径下执行 javah 命令，应该在源码根目录下执行。

错误二:

david@xmomx:hellojni$ cd ../../../

david@xmomx:src$ ls

com

david@xmomx:src$ javah -jni HelloJni

error: cannot access HelloJni

class file for HelloJni not found

javadoc: error - Class HelloJni not found.

Error: No classes were specified on the command line. Try -help.

错误原因：Classes 参数要使用完整类名，也就是说要加上包名

错误四：

david@xmomx:src$ javah -jni com/example/hellojni/HelloJni

javadoc: error - Illegal package name: "com/example/hellojni/HelloJni"

1 error

错误原因：完整类名格式错误

david@xmomx:src$ javah -jni com.example.hellojni.HelloJni

OK，编译通过。

如果还有错误，说是类找不到还是什么的，请尝试添加 -classpath . 参数。如下：

david@xmomx:src$ javah -jni -classpath . com.example.hellojni.HelloJni