java读取注册表

package test;

import java.io.*;


public class RegQuery {

private static final String REGQUERY_UTIL = "reg query ";
private static final String REGSTR_TOKEN = "REG_SZ";
private static final String REGDWORD_TOKEN = "REG_DWORD";

private static final String PERSONAL_FOLDER_CMD = REGQUERY_UTIL +
"\"HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\"
+ "Explorer\\Shell Folders\" /v Personal";
private static final String CPU_SPEED_CMD = REGQUERY_UTIL +
"\"HKLM\\HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0\""
+ " /v ~MHz";
private static final String CPU_NAME_CMD = REGQUERY_UTIL +
"\"HKLM\\HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0\""
+ " /v ProcessorNameString";
private static final String HTTP_DEFAULT_BROWSERURI = REGQUERY_UTIL +
"\"HKEY_CLASSES_ROOT\\http\\shell\\open\\command\""
+"" ;//http\\shell\\open\\ddeexec\\Topic
private static final String HTTP_DEFAULT_BROWSERNAME = REGQUERY_UTIL +
"\"HkEY_CLASSES_ROOT\\http\\shell\\open\\ddeexec\\Topic\""
+"" ;
public static String getCurrentUserPersonalFolderPath() {
try {
Process process = Runtime.getRuntime().exec(PERSONAL_FOLDER_CMD);
StreamReader reader = new StreamReader(process.getInputStream());

reader.start();
process.waitFor();
reader.join();

String result = reader.getResult();
int p = result.indexOf(REGSTR_TOKEN);

if (p == -1)
return null;

return result.substring(p + REGSTR_TOKEN.length()).trim();
}
catch (Exception e) {
return null;
}
}

public static String getCPUSpeed() {
try {
Process process = Runtime.getRuntime().exec(CPU_SPEED_CMD);
StreamReader reader = new StreamReader(process.getInputStream());

reader.start();
process.waitFor();
reader.join();

String result = reader.getResult();
int p = result.indexOf(REGDWORD_TOKEN);

if (p == -1)
return null;

// CPU speed in Mhz (minus 1) in HEX notation, convert it to DEC
String temp = result.substring(p + REGDWORD_TOKEN.length()).trim();
return Integer.toString
((Integer.parseInt(temp.substring("0x".length()), 16) + 1));
}
catch (Exception e) {
return null;
}
}

public static String getCPUName() {
try {

Process process = Runtime.getRuntime().exec(HTTP_DEFAULT_BROWSERURI);
StreamReader reader = new StreamReader(process.getInputStream());

reader.start();
process.waitFor();
reader.join();

String result = reader.getResult();
int p = result.indexOf(REGSTR_TOKEN);

if (p == -1)
return null;

return result.substring(p + REGSTR_TOKEN.length()).trim();
}
catch (Exception e) {
return null;
}
}

static class StreamReader extends Thread {
private InputStream is;
private StringWriter sw;

StreamReader(InputStream is) {
this.is = is;
sw = new StringWriter();
}

public void run() {
try {
int c;
while ((c = is.read()) != -1)
sw.write(c);
}
catch (IOException e) { ; }
}

String getResult() {
return sw.toString();
}
}

public static void main(String s[]) {
System.out.println("Personal directory : "
+ getCurrentUserPersonalFolderPath());
System.out.println("CPU Name : " + getCPUName());
System.out.println("CPU Speed : " + getCPUSpeed() + " Mhz");
}
}