如何替换指定jar中的class文件
void backupJar(File fileFrom) throws IOException {
JarEntry jarEntry;
byte[] buffer = new byte[1024];
JarInputStream jarIn;
JarOutputStream jarOut;
JarFile jarfile;
Manifest manifest;
backFile = new File(fileFrom.getParentFile(), fileFrom.getName()
.replace( ".jar ", "_v1.jar "));
if (!backFile.exists())
backFile.createNewFile();
jarfile = new JarFile(fileFrom);
manifest = jarfile.getManifest();
jarIn = new JarInputStream(new FileInputStream(fileFrom));
jarOut = new JarOutputStream(new FileOutputStream(backFile), manifest);
while ((jarEntry = jarIn.getNextJarEntry()) != null) {
if ( "META-INF/MANIFEST.MF ".equals(jarEntry.getName()))
continue;
jarOut.putNextEntry(jarEntry);
int read;
while ((read = jarIn.read(buffer)) != -1) {
jarOut.write(buffer, 0, read);
}
jarOut.closeEntry();
}
jarOut.flush();
jarOut.close();
jarIn.close();
}
通过上面的代码,我可以成功复制一个jar文件
但现在的问题是,我需要将原来jar文件中的某几个class更新为现在工程下的source目录中的的class文件,需要如何操作,我是这样考虑的,但是总是异常无法得到正确结果,还望高手能够帮助解决问题!!!
void updataFile(File fileFrom) throws IOException {
JarEntry jarEntry;
byte[] buffer = new byte[1024];
JarInputStream jarIn;
JarOutputStream jarOut;
JarFile jarfile;
Manifest manifest;
File modifyFile = new File(fileFrom.getParentFile(), fileFrom.getName()
.replace( ".jar ", "_v2.jar "));
if (!modifyFile.exists())
modifyFile.createNewFile();
jarfile = new JarFile(fileFrom);
manifest = jarfile.getManifest();
jarIn = new JarInputStream(new FileInputStream(fileFrom));
jarOut = new JarOutputStream(new FileOutputStream(modifyFile), manifest);
while ((jarEntry = jarIn.getNextJarEntry()) != null) {
String jarName = jarEntry.getName();
if ( "META-INF/MANIFEST.MF ".equals(jarName))
continue;
jarOut.putNextEntry(jarEntry);
if (updateEntry.contains(jarName)) {//如果是需要更新的class的话
String name = "source\\ "
+ jarName.substring(jarName.lastIndexOf( "/ ") + 1);
DataInputStream temp = new DataInputStream(new FileInputStream(name));
int read;
while ((read = temp.read(buffer)) != -1) {
jarOut.write(buffer, 0, read);
System.out.println(buffer);
}
} else {
int read;
while ((read = jarIn.read(buffer)) != -1)
jarOut.write(buffer, 0, read);
System.out.println( "---class--2--------> "
+ jarEntry.getName());
}
jarOut.closeEntry();
}
jarOut.flush();
jarOut.close();
jarIn.close();
}
[解决办法]
我没用过其他方法更新
只用
jar xvf ***.jar
替换后
jar cvf ***.jar *.*
LZ找到好方法一定要通知我哦
[解决办法]
因为jar文件是一个压缩包,可以先进行解压放到一个临时目录里面,把所需要的文件替换后,再行压缩成jar文件.
[解决办法]