java怎样生成32位全是整形的主键_Java生成32位全局唯一id

工具类实现代码如下：

import java.io.IOException;

import java.net.InetAddress;

import java.security.SecureRandom;

import java.text.SimpleDateFormat;

import java.util.Date;

import java.util.Random;

import java.util.concurrent.atomic.AtomicLong;

import org.apache.commons.lang.StringUtils;

/**

* @ClassName: UniqId

* @Description: 生成32位全局唯一id

*/

public class UniqId {

private static UniqId me = new UniqId();

private String hostAddr;

private final Random random = new SecureRandom();

private final UniqTimer timer = new UniqTimer();

private boolean isOutputInfo = false;

private UniqId() {

try {

final InetAddress addr = InetAddress.getLocalHost();

hostAddr = addr.getHostAddress();

}

catch (final IOException e) {

System.err.println("[UniqID] Get HostAddr Error"+e);

hostAddr = String.valueOf(System.currentTimeMillis());

}

if (null == hostAddr || hostAddr.trim().length() == 0 || "127.0.0.1".equals(hostAddr)) {

hostAddr = String.valueOf(System.currentTimeMillis());

}

hostAddr = hostAddr.substring(hostAddr.length()-2).replace(".", "0");

if(isOutputInfo){

System.out.println("[UniqID]hostAddr is:" + hostAddr + "----length:"+hostAddr.length());

}

}

/**

* 获取UniqID实例

*

* @return UniqId

*/

public static UniqId getInstance() {

me.isOutputInfo = false;

return me;

}

/**

* 获取UniqID实例

*

* @return UniqId

*/

public static UniqId getInstanceWithLog() {

me.isOutputInfo = true;

return me;

}

/**

* 获得不会重复的毫秒数

*

* @return 不会重复的时间

*/

public String getUniqTime() {

String time = timer.getCurrentTime();

if(isOutputInfo){

System.out.println("[UniqID.getUniqTime]" + time +"----length:"+ time.length());

}

return time;

}

/**

* 获得UniqId

*

* @return uniqTime-randomNum-hostAddr-threadId

*/

public String getUniqID() {

final StringBuffer sb = new StringBuffer();

final String t = getUniqTime();

int randomNumber = random.nextInt(8999999) + 1000000;

sb.append(t);

sb.append(hostAddr);

sb.append(getUniqThreadCode());

sb.append(randomNumber);

if (isOutputInfo) {

System.out.println("[UniqID.randomNumber]" + randomNumber+"----length:"+String.valueOf(randomNumber).length());

System.out.println("[UniqID.getUniqID]" + sb.toString()+"----length:"+String.valueOf(sb).length());

}

return sb.toString();

}

public String getUniqThreadCode(){

String threadCode = StringUtils.left(String.valueOf(Thread.currentThread().hashCode()),9);

if (isOutputInfo) {

System.out.println("[UniqID.getUniqThreadCode]" +threadCode+"----length:"+threadCode.length());

}

return StringUtils.leftPad(threadCode, 9, "0");

}

/**

* 实现不重复的时间

*/

private class UniqTimer {

private final AtomicLong lastTime = new AtomicLong(System.currentTimeMillis());

public String getCurrentTime() {

if(!timestamp2Date(this.lastTime.incrementAndGet()).equals(timestamp2Date(System.currentTimeMillis()))){

lastTime.set(System.currentTimeMillis()+random.nextInt(10000));

}

return timestamp2Datetimes(this.lastTime.incrementAndGet());

}

}

/**

* 规范化日期，规范成yyyy-MM-dd

* @param timestamp

* @return

*/

public static String timestamp2Date(long timestamp){

SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");

return dateFormat.format(new Date(timestamp * 1000));

}

private static String timestamp2Datetimes(long timestamp){

SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMddHHmmss");

return dateFormat.format(new Date(timestamp));

}

}

测试代码如下：

package com.test;

public class test {

public static void main(String[] args) {

//打印生成过程

UniqId.getInstanceWithLog().getUniqID();

//建议如下使用

//String uid = UniqId.getInstance().getUniqID();

//System.out.println(uid);

//System.out.println(uid.length());

}

}

上述代码依赖org.apache.commons.lang.StringUtils，介绍如下两种依赖的方式：

方式一：Maven项目的依赖

如果你的项目是maven项目，那么请确保项目的pom.xml有如下依赖：

commons-lang 或者commons-lang3