import java.util.HashMap;
/**
* @author ashang.peng@aliyun.com
* @date 二月 07, 2017
*/
public class IpMap {
// 待路由的Ip列表,Key代表Ip,Value代表该Ip的权重
public static HashMap<String, Integer> serverWeightMap =
new HashMap<String, Integer>();
static
{
serverWeightMap.put("192.168.1.100", 1);
serverWeightMap.put("192.168.1.101", 1);
// 权重为4
serverWeightMap.put("192.168.1.102", 4);
serverWeightMap.put("192.168.1.103", 1);
serverWeightMap.put("192.168.1.104", 1);
// 权重为3
serverWeightMap.put("192.168.1.105", 3);
serverWeightMap.put("192.168.1.106", 1);
// 权重为2
serverWeightMap.put("192.168.1.107", 2);
serverWeightMap.put("192.168.1.108", 1);
serverWeightMap.put("192.168.1.109", 1);
serverWeightMap.put("192.168.1.110", 1);
}
}
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
/**
* @author ashang.peng@aliyun.com
* @date 二月 07, 2017
*/
class RoundRobin {
private static Integer pos = 0;
public static String getServer()
{
// 重建一个Map,避免服务器的上下线导致的并发问题
Map<String, Integer> serverMap =
new HashMap<String, Integer>();
serverMap.putAll(IpMap.serverWeightMap);
// 取得Ip地址List
Set keySet = serverMap.keySet();
ArrayList keyList = new ArrayList();
keyList.addAll(keySet);
String server = null;
synchronized (pos)
{
// if (pos > keySet.size()) 謝謝@WO還在這兒的提醒,
// 應該為**-1否則確實會出現IndexOutOfBoundsException
if (pos > keySet.size()-1)
pos = 0;
server = keyList.get(pos);
pos ++;
}
return server;
}
}
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
/**
* @author ashang.peng@aliyun.com
* @date 二月 07, 2017
*/
class Random {
public static String getServer()
{
// 重建一个Map,避免服务器的上下线导致的并发问题
Map<String, Integer> serverMap =
new HashMap<String, Integer>();
serverMap.putAll(IpMap.serverWeightMap);
// 取得Ip地址List
Set keySet = serverMap.keySet();
ArrayList keyList = new ArrayList();
keyList.addAll(keySet);
java.util.Random random = new java.util.Random();
int randomPos = random.nextInt(keyList.size());
return keyList.get(randomPos);
}
}
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
/**
* @author ashang.peng@aliyun.com
* @date 二月 07, 2017
*/
class Hash {
public static String getServer()
{
// 重建一个Map,避免服务器的上下线导致的并发问题
Map<String, Integer> serverMap =
new HashMap<String, Integer>();
serverMap.putAll(IpMap.serverWeightMap);
// 取得Ip地址List
Set keySet = serverMap.keySet();
ArrayList keyList = new ArrayList();
keyList.addAll(keySet);
// 在Web应用中可通过HttpServlet的getRemoteIp方法获取
String remoteIp = "127.0.0.1";
int hashCode = remoteIp.hashCode();
int serverListSize = keyList.size();
int serverPos = hashCode % serverListSize;
return keyList.get(serverPos);
}
}
import java.util.*;
/** * @author ashang.peng@aliyun.com * @date 二月 07, 2017 */
class WeightRoundRobin {
private static Integer pos;
public static String getServer()
{
// 重建一个Map,避免服务器的上下线导致的并发问题
Map<String, Integer> serverMap =
new HashMap<String, Integer>();
serverMap.putAll(IpMap.serverWeightMap);
// 取得Ip地址List
Set<String> keySet = serverMap.keySet();
Iterator<String> iterator = keySet.iterator();
List<String> serverList = new ArrayList<String>();
while (iterator.hasNext())
{
String server = iterator.next();
int weight = serverMap.get(server);
for (int i = 0; i < weight; i++)
serverList.add(server);
}
String server = null;
synchronized (pos)
{
if (pos > keySet.size())
pos = 0;
server = serverList.get(pos);
pos ++;
}
return server;
}
}
import java.util.*;
/** * @author ashang.peng@aliyun.com * @date 二月 07, 2017 */
class WeightRandom {
public static String getServer()
{
// 重建一个Map,避免服务器的上下线导致的并发问题
Map<String, Integer> serverMap =
new HashMap<String, Integer>();
serverMap.putAll(IpMap.serverWeightMap);
// 取得Ip地址List
Set<String> keySet = serverMap.keySet();
Iterator<String> iterator = keySet.iterator();
List<String> serverList = new ArrayList<String>();
while (iterator.hasNext())
{
String server = iterator.next();
int weight = serverMap.get(server);
for (int i = 0; i < weight; i++)
serverList.add(server);
}
java.util.Random random = new java.util.Random();
int randomPos = random.nextInt(serverList.size());
return serverList.get(randomPos);
}
}
作者:犊子
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