bakmysql.java

一个学生选课系统

package com.student.dao;


import java.io.BufferedReader; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.FileOutputStream; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
import java.io.OutputStream; 
import java.io.OutputStreamWriter; 
import java.util.ArrayList;


public class BakMysql { 

//main的方法，主要是我用于测试的，是想着取得CLASS的路径，然后备份的文件写在服务器的类路径下 
	public static void main(String[] args) { 
		BakMysql bk = new BakMysql(); 
		/*System.out.println(Thread.currentThread().getContextClassLoader().getResource(""));     
  		System.out.println(BakMysql.class.getClassLoader().getResource(""));  
  		System.out.println(ClassLoader.getSystemResource("")); 
  		System.out.println(BakMysql.class.getResource(""));        
  		System.out.println(BakMysql.class.getResource("/")); //Class文件所在路径  
  		System.out.println(new File("/").getAbsolutePath());        
  		System.out.println(System.getProperty("user.dir"));    */ 
        //bk.backup(); 
        //bk.load(); 
        //System.out.println(bk.backupMySqlToFile()); 
		ArrayList ary=bk.getLog();
		for(int i=0;i<ary.size();i++)
		{
		     System.out.println(ary.get(i));
		}
    } 


//backup方法是备份数据库到服务器地址 
    public void backup() { 
        try { 
        	//System.getProperty("user.dir") + 
        String filePath ="D:\\workspace\\StudentProject\\mydata.sql";//BakMysql.class.getResource("").toString(); 
        System.out.println(filePath); 
            Runtime rt = Runtime.getRuntime(); 
            // 调用 mysql 的 cmd: 
            Process child = rt.exec("mysqldump  -uroot -p342 mydata");// 设置导出编码为utf8。这里必须是utf8 
           //注意这一句，是指运行mysqldump命令，后面跟的是登录名和登录的密码，接着后面的是指备份的数据库的名字，到此结束，以此生成一个执行的进程，取得此进程的输出流到我们要备份的文件 
            // 把进程执行中的控制台输出信息写入.sql文件，即生成了备份文件。注：如果不对控制台信息进行读出，则会导致进程堵塞无法运行 
            InputStream in = child.getInputStream();// 控制台的输出信息作为输入流 
                       
            InputStreamReader xx = new InputStreamReader(in, "utf8");// 设置输出流编码为utf8。这里必须是utf8，否则从流中读入的是乱码 
           
            String inStr; 
            StringBuffer sb = new StringBuffer(""); 
            String outStr; 
            // 组合控制台输出信息字符串 
            BufferedReader br = new BufferedReader(xx); 
            while ((inStr = br.readLine()) != null) { 
                sb.append(inStr + "\r\n"); 
            } 
            outStr = sb.toString();//备份出来的内容是一个字条串 
           
            // 要用来做导入用的sql目标文件： 
            FileOutputStream fout = new FileOutputStream(filePath); 
            OutputStreamWriter writer = new OutputStreamWriter(fout, "utf8"); 
            writer.write(outStr);//写文件 
            // 注：这里如果用缓冲方式写入文件的话，会导致中文乱码，用flush()方法则可以避免 
            writer.flush(); 

            // 别忘记关闭输入输出流 
            in.close(); 
            xx.close(); 
            br.close(); 
            writer.close(); 
            fout.close(); 

            System.out.println(""); 

        } catch (Exception e) { 
            e.printStackTrace(); 
        } 

    } 
    




    public String backupMySqlToFile() { 
    String outStr = ""; 
    try { 
        Runtime rt = Runtime.getRuntime(); 
            Process child = rt.exec("mysqldump  -uroot -p342 mydata");// 设置导出编码为utf8。这里必须是utf8在此要注意，有时会发生一个mysqldump: Got error: 1045的错误，此时mysqldump必须加上你要备份的数据库的IP地址，即mysqldump -h192.168.0.1 -uroot -pmysql dbname，今天我就遇到了这样的问题，呵呵             // 把进程执行中的控制台输出信息写入.sql文件，即生成了备份文件。注：如果不对控制台信息进行读出，则会导致进程堵塞无法运行 
            InputStream in = child.getInputStream();// 控制台的输出信息作为输入流 
            InputStreamReader xx = new InputStreamReader(in, "utf8");// 设置输出流编码为utf8。这里必须是utf8，否则从流中读入的是乱码 
            String inStr; 
            StringBuffer sb = new StringBuffer(""); 
            // 组合控制台输出信息字符串 
            BufferedReader br = new BufferedReader(xx); 
            while ((inStr = br.readLine()) != null) { 
                sb.append(inStr + "\r\n"); 
            } 
            outStr = sb.toString(); 
            in.close(); 
            xx.close(); 
            br.close(); 

        } catch (Exception e) { 
            e.printStackTrace(); 
        } 
        return outStr; 
    } 
    //从服务器的备份文件进行恢复
    public void load() { 
        try { 
            String fPath = "D:\\workspace\\StudentProject\\mydata.sql"; 
            Runtime rt = Runtime.getRuntime(); 
            Process child = rt.exec("mysql -uroot -p342 mydata"); 
            OutputStream out = child.getOutputStream();//控制台的输入信息作为输出流 
            String inStr; 
            StringBuffer sb = new StringBuffer(""); 
            String outStr; 
            BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(fPath), "utf8")); 
            while ((inStr = br.readLine()) != null) { 
                sb.append(inStr + "\r\n"); 
            } 
            outStr = sb.toString(); 
            OutputStreamWriter writer = new OutputStreamWriter(out, "utf8"); 
            writer.write(outStr); 
            // 注：这里如果用缓冲方式写入文件的话，会导致中文乱码，用flush()方法则可以避免 
            writer.flush(); 
            out.close(); 
            br.close(); 
            writer.close(); 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 

    } 
//查看日志文件
    public static  ArrayList getLog()
    {
    	ArrayList logs=new ArrayList();
    	 try { 
             String fPath = "D:\\workspace\\StudentProject\\log.log"; 
             //Runtime rt = Runtime.getRuntime(); 
             //Process child = rt.exec("mysql -uroot -p342 mydata"); 
             //OutputStream out = child.getOutputStream();//控制台的输入信息作为输出流 
             String inStr; 
             //StringBuffer sb = new StringBuffer(""); 
             //String outStr; 
             BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(fPath), "utf8")); 
             while ((inStr = br.readLine()) != null) { 
                 logs.add(inStr);
             } 
             //outStr = sb.toString(); 
             //OutputStreamWriter writer = new OutputStreamWriter(out, "utf8"); 
             //writer.write(outStr); 
             // 注：这里如果用缓冲方式写入文件的话，会导致中文乱码，用flush()方法则可以避免 
             //writer.flush(); 
             //out.close(); 
             //br.close(); 
             //writer.close(); 
         } catch (Exception e) { 
             e.printStackTrace(); 
         } 
    	return logs;
    }
//用户端恢复数据，直接传一个上传的文件给这个方法，就可以对数据库进行恢复了 
    public void restoreMysqlFromFile(File f) { 
        try { 
            FileInputStream fis = new FileInputStream(f); 
            Runtime rt = Runtime.getRuntime(); 
            Process child = rt.exec("mysql -uroot -pmysql dbname");//这里执行的是mysql命令，用户名，密码以及要恢复的数据库，命令执行完后会从我们上传的文件里面读取要执行的内容 
            OutputStream out = child.getOutputStream();//控制台的输入信息作为输出流 
            String inStr; 
            StringBuffer sb = new StringBuffer(""); 
            String outStr; 
            BufferedReader br = new BufferedReader(new InputStreamReader(fis, "utf8")); 
            while ((inStr = br.readLine()) != null) { 
                sb.append(inStr + "\r\n"); 
            } 
            outStr = sb.toString(); 
            OutputStreamWriter writer = new OutputStreamWriter(out, "utf8"); 
            writer.write(outStr); 
            // 注：这里如果用缓冲方式写入文件的话，会导致中文乱码，用flush()方法则可以避免 
            writer.flush(); 
            out.close(); 
            br.close(); 
            writer.close(); 
            fis.close(); 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 

    } 

}