关于hashMap的几种遍历方法

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package Futures;

//这是一个期货信息类
public class FutureStockInfo {
private String futureInfo;
private char marketNo;
private double lastPrice;
public FutureStockInfo() {

}

public FutureStockInfo(String futureInfo, char marketNo, double lastPrice) {
this.futureInfo = futureInfo;
this.marketNo = marketNo;
this.lastPrice = lastPrice;
}


public String getFutureInfo() {
return futureInfo;
}


public void setFutureInfo(String futureInfo) {
this.futureInfo = futureInfo;
}


public char getMarketNo() {
return marketNo;
}


public void setMarketNo(char marketNo) {
this.marketNo = marketNo;
}


public double getLastPrice() {
return lastPrice;
}


public void setLastPrice(double lastPrice) {
this.lastPrice = lastPrice;
}


@Override
public String toString() {
return "FutureStockInfo [futureInfo=" + futureInfo + ", marketNo=" + marketNo + ", lastPrice=" + lastPrice
+ "]";
}

}




package Futures;


import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;


public class Test {

public static void test()
{
FutureStockInfo info = new FutureStockInfo();
info.setFutureInfo("IF1701");
info.setMarketNo('7');
info.setLastPrice(6000.00);
System.out.println(info.toString());
}

public static void test1()
{
ArrayList al = new ArrayList(1000);
for(int index=0; index<1000; index++){
FutureStockInfo info = new FutureStockInfo("IF1"+index, '7', 6000+index);
al.add(info);
}

for(int index=0; index<1000; index++){
FutureStockInfo info = (FutureStockInfo) al.get(index);
System.out.println(info);
}
}

public static void test2()
{
Map<String, FutureStockInfo> map = new HashMap<String, FutureStockInfo>();
for(int index=0; index<100; index++){
String key = "IF1" + index;
FutureStockInfo info = new FutureStockInfo(key, '7', 6000+index);
map.put(key, info);
}
System.out.println("添加100条记录完毕。。。。。。");

//第一种遍历HashMap的方法
//for (String key : map.keySet() ) {  
// System.out.println("FutureStockInfo= "+ key + " and value= " + map.get(key).toString());  
//}  

//使用Iterrator方法进行遍历
//Iterator<Map.Entry<String, FutureStockInfo>> it = map.entrySet().iterator();  
//while (it.hasNext()) {  
// Map.Entry<String, FutureStockInfo> entry = it.next();  
// System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());  
//} 

//使用entrySet进行程序的遍历
//for (Map.Entry<String, FutureStockInfo> entry : map.entrySet()) {  
// System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue().toString());  
// }  

//使用values进行所有value的方法遍历
for (FutureStockInfo v : map.values()) {  
System.out.println("value= " + v.toString());  

}

    public static void main(String[] args)
    {
    test2();
    }
}


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