如何从 jar 文件中获取 Manifest.mf 文件内容

Question

I have a jar file named " mail.jar " .I have extracted the jar file through java code. Now I have manifest file present under "D:/Test/META-INF/MANIFEST.MF" location. This is the image of Manifest.mf file content . Any way I am able to read to Manifest file by the help of FileReader and BufferedReader and print it to the console. In the manifest file ,below specifications r present. (1)Manifest-Version: (2)Archiver-Version: (3)Created-By: (4) Export-Package:

Now my doubt is how to get all the package list under Export-Package: tag only . Can anyone help me here ?? Any help will be appreciated.

O/P should display like below screen shot. Expected O/P screen shot

Regards, AD

Answer 1

Hi solomon & PeterMmm, Thanks for your help. now I am able to access the manifest file content for specific attribute. Below is the code snippet I am using:-

public class ReadmanifestFile {
public String getManifestAttributes() throws IOException {
    String value = null;
    File file = new File("G:/AD/JAR_FILES/mail.jar");
    if (file.isFile()) {
        JarFile jarfile = new JarFile(file);
        Manifest manifest = jarfile.getManifest();
        Attributes attributes = manifest.getMainAttributes();
        value = attributes.getValue("Export-Package");
        String[] arr = value.split(";");
        for (int i = 0; i < arr.length; i++) {
            System.out.println(arr[i]);
        }
    }
    return value;
}

}

click the below for Output for above code snippet:- Output

I think this is right way to do.Plz let me know if I can improve the code snippet in any of the other ways.

regards, AD