MyEclipse+Tomcat环境下Java调用DLL问题
windows xp系统，在MyEclipse下做一个Java调用dll的程序
在src下面编写javabean代码：
javacall.java
public class javacall {
static
{
System.loadLibrary("calldll");
}
public native static int add(int i, int k); //在calldll.dll实现
public static void main(String[] args)
{
javacall jc = new javacall();
System.out.println(jc.add(3,4));
}
}
编译生成javacall.class文件，生成javacall.h文件
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
在VC6.0下生成dll文件，程序如下
#include <jni.h>
#include "javacall.h"
JNIEXPORT jint JNICALL Java_javacall_add (JNIEnv *, jclass, jint a,jint b)
{
return a*b;
}
在命令行下直接运行java javacall结果正确
如果这时候直接在MyEclipse下run application会报错：
java.lang.UnsatisfiedLinkError: no calldll in java.library.path
at java.lang.ClassLoader.loadLibrary(Unknown Source)
at java.lang.Runtime.loadLibrary0(Unknown Source)
at java.lang.System.loadLibrary(Unknown Source)
at javacall.<clinit>(javacall.java:4)
Exception in thread "main"
这时在run-java application-arguments-VM arguments下面添加
-Djava.library.path=E:\MyEclipse\workspace\jspcall\WebRoot\WEB-INF\classes
这个路径是calldll.dll的存放路径，也是javacall.class所在路径
然后运行成功，得到想要的结果12
最后我在WebRoot下面编写call.jsp文件
<%@ page contentType="text/html; charset=GBK" %>
<html>
<head>
<title>
Jsp调用DLL例子
</title>
</head>
<jsp:useBean id="JBean" scope="page" class="javacall" />
<body>
<h1>
<%=JBean.add(3,4)%>
</h1>
</body>
</html>
配置到tomcat6.0下，
工程结构大致为jspcall在C:\Tomcat 6.0\webapps
call.jsp在C:\Tomcat 6.0\webapps\jspcall
javacall.class跟calldll.dll都在
C:\Tomcat 6.0\webapps\jspcall\WEB-INF\classes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
然后输入http://localhost:8080/jspcall/call.jsp
出现错误：
HTTP Status 500 -
--------------------------------------------
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: Unable to compile class for JSP:
An error occurred at line: 8 in the jsp file: /call.jsp
javacall cannot be resolved to a type
5: Jsp调用DLL例子
6: </title>
7: </head>
8: <jsp:useBean id="JBean" scope="page" class="javacall" />
9: <body>
10: <h1>
11: <%=JBean.add(3,4)%>
An error occurred at line: 8 in the jsp file: /call.jsp
javacall cannot be resolved to a type
5: Jsp调用DLL例子
6: </title>
7: </head>
8: <jsp:useBean id="JBean" scope="page" class="javacall" />
9: <body>
10: <h1>
11: <%=JBean.add(3,4)%>
An error occurred at line: 8 in the jsp file: /call.jsp
javacall cannot be resolved to a type
5: Jsp调用DLL例子
6: </title>
7: </head>
8: <jsp:useBean id="JBean" scope="page" class="javacall" />
9: <body>
10: <h1>
11: <%=JBean.add(3,4)%>
Stacktrace:
org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:92)
org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:330)
org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:423)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:308)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:286)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:273)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:566)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
有人说：
windows下在catalina.bat里
set JAVA_OPTS=%JAVA_OPTS%
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
-Djava.util.logging.config.file="%CATALINA_BASE%\conf\logging.properties"
"-Djava.library.path=/"$你的dll的位置"
不知道是不是版本的问题，我这里tomcat6.0下没有catalina.bat
但是在tomcat的config（Apache Tomcat Properties）-java-java options
下有
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
-Djava.util.logging.config.file=C:\Tomcat 6.0\conf\logging.properties
然后我又添加了
-Djava.library.path=C:\Tomcat 6.0\webapps\jspcall\WEB-INF\classes
错误依然
这个问题困扰我三天了，下午找一个朋友也没能解决
对这个了解的牛人帮忙调试一下，不胜感激
[解决办法]
如果要自定义DLL文件路径，例如将dll文件存放在E:\DLL那么编辑tomcat-bin--catalina.bat
在set JAVA_OPTS=%JAVA_OPTS%
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
-Djava.util.logging.config.file="%CATALINA_BASE%\conf\logging.properties"
后面添加-Djava.library.path="E:/DLL"
我的异常网推荐解决方案：The server encountered an internal error () that prevented it from fulfilling this request.,http://www.myexception.cn/java-web/317.html
我的异常网推荐解决方案：org.apache.jasper.JasperException: Unable to compile class,http://www.myexception.cn/j2ee/2308.html
