7.使用ProcessBuilder执行本地命令
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* 在J2SE5.0之前使用Runtime的exec方法执行本地命令.
* 在J2Se5.0之后,可以使用ProcessBuilder执行本地命令
* 它提供的功能更加丰富,能够设置设置工作目录、环境变量等
* 本例PorcessBuilder执行Windows操作系统的"ipconfig/all"命令,获取本机网卡的MAC地址
*/
/**关键技术剖析
* 用本命令名和命令的参数选项构造ProcessBuilder对象,它的start方法执行命令,启动一个进程,返回一个Process对象
* ProcessBuilder的environment方法获得运行进程的环境变量,得到一个Map,可以修改环境变量
* ProcessBuilder的directory方法切换工作目录
* Process的getInputStream方法获得进程的标准输出流,getErrorStream方法获得进程的错误输出流
*/
public class UsingProcessBuilder {
/**获取Windows系统下的网卡的MAC地址*/
public static List<String> getPhysicalAddress(){
Process p = null;
List<String> address = new ArrayList<String>(); //物理网卡列表
try{
p = new ProcessBuilder("ipconfig","/all").start(); //执行ipconfig/all命令
}catch(IOException e){
return address;
}
byte[] b = new byte[1024];
int readbytes = -1;
StringBuffer sb = new StringBuffer();
//读取进程输出值
//在JAVA IO中,输入输出是针对JVM而言,读写是针对外部数据源而言
InputStream in = p.getInputStream();
try{
while((readbytes = in.read(b)) != -1){
sb.append(new String(b,0,readbytes));
}
}catch(IOException e1){
}finally {
try{
in.close();
}catch (IOException e2){
}
}
//以下是分析输出值,得到物理网卡
String rtValue = sb.toString();
int i = rtValue.indexOf("Physical Address. . . . . . . . . :");
while (i > 0){
rtValue = rtValue.substring(i + "Physical Address. . . . . . . . . :".length());
address.add(rtValue.substring(1,18));
i = rtValue.indexOf("Physical Address. . . . . . . . . :");
}
return address;
}
/**执行自定义的一个命令,该命令放在C:/temp下,并且需要两个环境变量的支持*/
public static boolean executeMyCommand1(){
//创建系统进程创建器
ProcessBuilder pb = new ProcessBuilder("myCommand","myArg1","myArg2");
Map<String, String> env = pb.environment(); //获得进程的环境
//设置和去除环境变量
env.put("VAR1", "myValue");
env.remove("VAR0");
env.put("VAR2", env.get("VAR1") + ";");
//迭代环境变量,获取属性名和属性值
Iterator it=env.keySet().iterator();
String sysatt = null;
while(it.hasNext())
{
sysatt = (String)it.next();
System.out.println("System Attribute:"+sysatt+"="+env.get(sysatt));
}
pb.directory(new File("C:/temp"));
try{
Process p = pb.start(); //得到进程实例
//等待进程执行完毕
if(p.waitFor() != 0){
//如果进程运行结果不为0,表示进程是错误退出的
//获得进程实例的错误输出
InputStream error = p.getErrorStream();
//do something
}
InputStream sdin = p.getInputStream(); //获得进程实例的标准输出
//do something
}catch(IOException e){
}catch(InterruptedException e){
}
return true;
}
public static void executeMyCommand2(){
ProcessBuilder pb = null;
String sysatt = null;
try
{
//创建一个进程示例
pb = new ProcessBuilder("cmd.exe");
//获取系统参数并打印显示
Map<String, String> env = pb.environment();
Iterator it=env.keySet().iterator();
while(it.hasNext())
{
sysatt = (String)it.next();
System.out.println("System Attribute:"+sysatt+"="+env.get(sysatt));
}
//设置工作目录
pb.directory(new File("d://myDir"));
Process p = pb.start();
//将要执行的Windows命令写入
BufferedWriter bw=new BufferedWriter(newOutputStreamWriter(p.getOutputStream()));
//'/r/n'是必须写入的
bw.write("test.bat /r/n");
bw.write("ping -t www.yahoo.com.cn /r/n");
//flush()方法是必须调用的
bw.flush();
//将执行结果打印显示
InputStream is = p.getInputStream();
InputStreamReader isr = new InputStreamReader(is, "GBK");
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null)
{
System.out.println(line);
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public static void main(String[] args){
List<String> address = UsingProcessBuilder.getPhysicalAddress();
for(String add : address){
System.out.printf("物理网卡地址: %s%n",add);
}
executeMyCommand1();
executeMyCommand2();
}
}