读取，修改jar文件

读取，修改，操作，编辑，jar文件
文件选择 jarFileSelect()

    private void jarFileSelect(MouseEvent evt) {
        JFileChooser fileChooser = new JFileChooser(".");
        fileChooser.setDialogTitle("editFrame");
        fileChooser.setFileHidingEnabled(false);
        fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
        FileFilter filter = new FileNameExtensionFilter("jar文件", "jar");
        fileChooser.addChoosableFileFilter(filter);

        int choice = fileChooser.showOpenDialog(null);
        if (choice != JFileChooser.APPROVE_OPTION) {
            return;
        }
        contentTa.setText("");
        File file = fileChooser.getSelectedFile();
        jarFileTf.setText(file.getAbsolutePath());
    }

有效性校验 valid()

    private boolean valid() {
        boolean ret = false;
        if (!StringUtils.isEmpty(jarFileTf.getText()) && !StringUtils.isEmpty(fileTf.getText())) {
            ret = true;
        } else {
            contentTa.setText("不能为空");
        }
        return ret;
    }

根据stream获取byte getByte()

    //从输入取字节
    public byte[] getByte(java.io.InputStream s) {
        byte[] buffer = new byte[0];
        byte[] chunk = new byte[4096];
        int count;
        try {
            while ((count = s.read(chunk)) >= 0) {
                byte[] t = new byte[buffer.length + count];
                System.arraycopy(buffer, 0, t, 0, buffer.length);
                System.arraycopy(chunk, 0, t, buffer.length, count);
                buffer = t;
            }
            s.close();
        } catch (Exception e) {
        }
        return buffer;
    }

打开jar文件 open()

    private void open(MouseEvent evt) {
        try {
            if (!valid()) {
                return;
            }
            String jarFileName = jarFileTf.getText();
            String fileName = fileTf.getText();

            File file = new File(jarFileName);
            JarFile jarFile = new JarFile(file);
            TreeMap tm = new TreeMap();
            Enumeration es = jarFile.entries();
            while (es.hasMoreElements()) {
                JarEntry je = (JarEntry) es.nextElement();
                byte[] bytes = getByte(jarFile.getInputStream(je));
                tm.put(je.getName(), bytes);
                if (je.getName().contains(fileName)) {
                    String str = new String(bytes);
                    contentTa.setText(str);
                    break;
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
            contentTa.setText("出错了！！！，文件格式不对");
        }
        JOptionPane.showMessageDialog(rootPane, "打开完成");
    }

编辑 edit()

    private void edit(MouseEvent evt) {
        try {
            if (!valid()) {
                return;
            }
            String content = contentTa.getText();
            if (content == null || content.equals("")) {
                JOptionPane.showMessageDialog(rootPane, "不能为空");
                return;
            }
            String jarFileName = jarFileTf.getText();
            String fileName = fileTf.getText();
            
            File file = new File(jarFileName);
            
            JarFile jarFile = new JarFile(file);
            TreeMap tm = new TreeMap();
            Enumeration es = jarFile.entries();
            while (es.hasMoreElements()) {
                JarEntry je = (JarEntry) es.nextElement();
                byte[] bytes = getByte(jarFile.getInputStream(je));
                tm.put(je.getName(), bytes);
            }
            
            JarOutputStream out = new JarOutputStream(new FileOutputStream(file));
            Set set = tm.entrySet();
            Iterator it = set.iterator();
            while (it.hasNext()) {
                Map.Entry me = (Map.Entry) it.next();
                String name = (String) me.getKey();
                JarEntry jeNew = new JarEntry(name);
                out.putNextEntry(jeNew);
                byte[] b = (byte[]) me.getValue();
                if (name.contains(fileName)) {
                    b = content.getBytes();
                } else {
                }
                out.write(b, 0, b.length);
            }
            out.finish();
            out.close();
            JOptionPane.showMessageDialog(rootPane, "修改完成");
        } catch (Exception e) {
            e.printStackTrace();
            contentTa.setText("出错了！！！，文件格式不对");
        }

    }