Jar 忽略所有方法

Question

I was making a pretty simple jar to unzip a zip and run the jar that was inside of it. The problem I've run into is that it doesn't do anything at all.

This is the main, and only class file for the jar. The manifest does point correctly to it, and it loads without errors.

import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.io.FileWriter;
import java.io.BufferedWriter;
import java.io.BufferedOutputStream;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.FileOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.InputStreamReader;
import static java.lang.Integer.parseInt;
import java.net.URLConnection;
import java.net.URL;
import java.util.zip.ZipFile;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.Enumeration;
import sign.signlink;
import java.nio.file.*;
import java.io.FileReader;

    public class ClientUpdater {

    private String fileToExtractNew = "/client.zip";

    private String getJarDir() throws FileNotFoundException, IOException{
            String linebuf="",verStr="";
            FileInputStream fis = new FileInputStream("/runLocationURL.txt");
            BufferedReader br= new BufferedReader(new InputStreamReader(fis));
            while ((linebuf = br.readLine()) != null) {
                verStr = linebuf;
            }
            return verStr;
    }

    public static void main(String[] args) {
System.out.println("start");
    }

    private void unZip() {
    System.out.println("unzipping");
        try {
            ZipEntry zipEntry;
            //client
            BufferedInputStream bufferedInputStreamNew = new BufferedInputStream(new FileInputStream(this.fileToExtractNew));
            ZipInputStream zipInputStreamNew = new ZipInputStream(bufferedInputStreamNew);

            //client
            while ((zipEntry = zipInputStreamNew.getNextEntry()) != null) {
                String stringNew = zipEntry.getName();
                File fileNew = new File(this.getJarDir() + File.separator + stringNew);
                if (zipEntry.isDirectory()) {
                    new File(this.getJarDir() + zipEntry.getName()).mkdirs();
                    continue;
                }
                if (zipEntry.getName().equals(this.fileToExtractNew)) {
                    this.unzipNew(zipInputStreamNew, this.fileToExtractNew);
                    break;
                }
                new File(fileNew.getParent()).mkdirs();
                this.unzipNew(zipInputStreamNew, this.getJarDir() + zipEntry.getName());
            }
            zipInputStreamNew.close();
        }
        catch (Exception var1_2) {
            var1_2.printStackTrace();
        }
    }

    private void unzipNew(ZipInputStream zipInputStreamNew, String stringNew) throws IOException {
    System.out.println("unzipping new");
        FileOutputStream fileOutputStreamNew = new FileOutputStream(stringNew);
        byte[] arrby = new byte[4024];
        int n = 0;
        while ((n = zipInputStreamNew.read(arrby)) != -1) {
            fileOutputStreamNew.write(arrby, 0, n);
        }
        fileOutputStreamNew.close();
        Runtime.getRuntime().exec("java -jar " + getJarDir() + "/Project Pk Client.jar");
        System.exit(0);
    }
}

It shows the "Start" message, but not the other 2, so it never reaches those methods. Is it because they aren't being called? I'm still learning Java.

Answer 1

You actually have to call your other methods from main . Right now, all you are telling the computer to do is print start and then exit. Functions do not get called simply by existing.

It seems based on a quick glance that you just need to add unzip(); to your main function, right after the System.out.println line.

To do this, you need to say that those other methods are static , so you need to say private static void unZip() instead of private void unZip() . Do this for your other methods too.

import java.io.*;
import static java.lang.Integer.parseInt;
import java.net.URLConnection;
import java.net.URL;
import java.util.zip.ZipFile;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.Enumeration;
import sign.signlink;
import java.nio.file.*;

public class ClientUpdater {

    private String fileToExtractNew = "/client.zip";

    private static String getJarDir() throws FileNotFoundException, IOException{
        String linebuf="",verStr="";
        FileInputStream fis = new FileInputStream("/runLocationURL.txt");
        BufferedReader br= new BufferedReader(new InputStreamReader(fis));
        while ((linebuf = br.readLine()) != null) {
            verStr = linebuf;
        }
        return verStr;
    }

    public static void main(String[] args) {
        System.out.println("start");
        unZip();
    }

    private static void unZip() {
        System.out.println("unzipping");
        try {
            ZipEntry zipEntry;
            //client
            BufferedInputStream bufferedInputStreamNew = new BufferedInputStream(new FileInputStream(this.fileToExtractNew));
            ZipInputStream zipInputStreamNew = new ZipInputStream(bufferedInputStreamNew);

            //client
            while ((zipEntry = zipInputStreamNew.getNextEntry()) != null) {
                String stringNew = zipEntry.getName();
                File fileNew = new File(this.getJarDir() + File.separator + stringNew);
                if (zipEntry.isDirectory()) {
                    new File(this.getJarDir() + zipEntry.getName()).mkdirs();
                    continue;
                }
                if (zipEntry.getName().equals(this.fileToExtractNew)) {
                    this.unzipNew(zipInputStreamNew, this.fileToExtractNew);
                    break;
                }
                new File(fileNew.getParent()).mkdirs();
                this.unzipNew(zipInputStreamNew, this.getJarDir() + zipEntry.getName());
            }
            zipInputStreamNew.close();
        }
        catch (Exception var1_2) {
            var1_2.printStackTrace();
        }
    }

    private static void unzipNew(ZipInputStream zipInputStreamNew, String stringNew) throws IOException {
        System.out.println("unzipping new");
        FileOutputStream fileOutputStreamNew = new FileOutputStream(stringNew);
        byte[] arrby = new byte[4024];
        int n = 0;
        while ((n = zipInputStreamNew.read(arrby)) != -1) {
            fileOutputStreamNew.write(arrby, 0, n);
        }
        fileOutputStreamNew.close();
        Runtime.getRuntime().exec("java -jar " + getJarDir() + "/Project Pk Client.jar");
        System.exit(0);
    }
}