随机流修改文本内容

package com.oldboy.hbase;

import java.io.*;

public class Edit {
    public static void main(String[] args) throws IOException {

        File file = new File("G:\\MyVirtual\\CentOS-7-x86_64-Minimal-1611-111\\CentOS-7-x86_64-Minimal-1611-110-cl1-000003.vmdk");
//     modifyFileContent(file,"parentCID=6cb404c7","parentCID=9f767ebd");
        showText();
    }
    private static boolean modifyFileContent(File file, String oldstr, String newStr) {
        RandomAccessFile raf = null;
        try {
            raf = new RandomAccessFile(file, "rw");
            String line = null;
            long lastPoint = 0; //记住上一次的偏移量
            while ((line = raf.readLine()) != null) {
                final long ponit = raf.getFilePointer();
                if(line.contains(oldstr)){
                    String str=line.replace(oldstr, newStr);
                    raf.seek(lastPoint);
                    raf.writeBytes(str);
                }
                lastPoint = ponit;
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                raf.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return true;
    }
    public static void showText() throws IOException {
        File file = new File("G:\\MyVirtual\\CentOS-7-x86_64-Minimal-1611-111\\CentOS-7-x86_64-Minimal-1611-110-cl1-000003.vmdk");
        FileInputStream fis = new FileInputStream(file);
        InputStreamReader isr = new InputStreamReader(fis);
        BufferedReader br = new BufferedReader(isr);
        String str ;
        while ((str = br.readLine())!=null){
            if (str.contains("parentCID")){
                System.out.println(str);
            }
        }
    }
}