Java备份Oracle数据库

Java线程、Process、ProcessBuilder

2010 年 6 月 20 日

文章内容描述了使用Java执行外部Oracle导出命令备份数据库功能的示例，依据此例子进行修改制造一些bug，然后将会对Java外部命令这块会有一个更加清晰的认知(个人观点仅供参考，不许拍砖，哈)

小细节

·试着把innerTh.start()这段给注释掉，然后再把用户名或密码写错。
·有些程序是不会在命令行有输出的，比如最直接的plsqldev.exe、MindManager.exe
·试着把将要执行的命令改成我们本地相关.exe程序，如上面所例或干脆TM.exe试试。

回页首

代码示例:

package org.ybygjy.basic.oracle;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.nio.channels.Channels;
import java.nio.channels.FileChannel;
import java.nio.channels.ReadableByteChannel;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
/**
* java外部系统命令模式备份数据库
* @author WangYanCheng
* @version 2010-6-19
*/
public class BackupOracleDatabase {
/**
* 封装执行入口
*/
public void doWork() {
InnerClass innerInst =
new InnerClass(“DB_USER”, “DB_PASS”, “127.0.0.1:1521/ORCL”, “E:/dbback/BACK201006.DMP”);
Thread thInst = new Thread(innerInst);
thInst.start();
}
/**
* 用于分担执行命令
* @author WangYanCheng
* @version 2010-6-19
*/
class InnerClass implements Runnable {
/** 用户名 */
private String userName;
/** 密码 */
private String userPass;
/** 服务地址 */
private String serverAddr;
/** 输出文件路径 */
private String outFilePath;
/**
* constructor
* @param userName userName
* @param userPass userPass
* @param serverAddr 服务地址必须带<strong>端口</strong>/<strong>SID</strong>
* @param outFilePath outPath
*/
public InnerClass(String userName, String userPass, String serverAddr, String outFilePath) {
this.userName = userName;
this.userPass = userPass;
this.serverAddr = serverAddr;
this.outFilePath = outFilePath;
}
/**
* 提供执行的命令串
* @return commStr 命令串
*/
private List doBuildCommand() {
List rtnList = new ArrayList();
rtnList.add(“EXP”);
rtnList.add(“@USER@/@PASSWORD@@@SERVER@”.replaceAll(“@USER@”, this.userName)
.replaceAll(“@PASSWORD@”, this.userPass).replaceAll(“@SERVER@”, this.serverAddr));
rtnList.add(“FILE=/”@FILE@/””.replaceAll(“@FILE@”, this.outFilePath));
rtnList.add(“TABLES=(SY_TABLE_DEF)”);
return rtnList;
}
/**
* 构建ProcessBuilder实例
* @param workDir 当前进程工作目录
* @return pbInst ProcessBuilder实例
* @see ProcessBuilder
*/
private ProcessBuilder buildProcessBuilder(File workDir) {
new ProcessBuilder();
List commandArray = (doBuildCommand());
ProcessBuilder pbInst = new ProcessBuilder(commandArray);
pbInst.command(commandArray);
Map envMap = pbInst.environment();
envMap.clear();
envMap.putAll(System.getenv());
pbInst.directory(workDir);
pbInst.redirectErrorStream(true);
return pbInst;
}
/**
* 线程执行入口
*/
public void run() {
File tmpOutFile = new File(this.outFilePath);
File outDir = tmpOutFile.getParentFile();
ProcessBuilder pbInst = buildProcessBuilder(outDir);
try {
Process proInst = pbInst.start();
final InputStream ins = proInst.getInputStream();
File outFile = new File(outDir, “exp.log”);
outFile.createNewFile();
final FileChannel focInst = new FileOutputStream(outFile).getChannel();
Thread innerTh = new Thread() {
ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
public void run() {
ReadableByteChannel rbcObj = Channels.newChannel(ins);
try {
while (rbcObj.read(byteBuffer) != -1) {
byteBuffer.flip();
focInst.write(byteBuffer);
byteBuffer.clear();
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
};
// innerTh.setDaemon(true);
innerTh.start();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
}
/**
* 测试入口
* @param args 参数列表
*/
public static void main(String[] args) {
new BackupOracleDatabase().doWork();
}
}

个人收藏笔记记录

开通VIP