自定义的Key类需要重载equals, hashCode函数。。
package com.albert.test;
import java.util.Vector;
import java.util.HashMap;
/**
* @author tough_guy
*
*/
//对于自定义的key， 需要重载hashCode函数和equals函数
class IPSegment
{
long ip_s;
long ip_e;
int p;
IPSegment Reset(long f1, long f2, int f3)
{
ip_s = f1;
ip_e = f2;
p = f3;
return this;
}
public boolean equals(Object so)
{
if(! (so instanceof IPSegment))
return false;
if(this.ip_s == ((IPSegment)so).ip_s && this.ip_e == ((IPSegment)so).ip_e && this.p == ((IPSegment)so).p)
return true;
else
return false;
}
public int hashCode()
{
return (int)(ip_s + ip_e + p);
}
}
public class TestString {
Vector<IPSegment> vi = new Vector<IPSegment>();
HashMap<IPSegment, Integer> hii = new HashMap<IPSegment, Integer>();
HashMap<String, String> hss = new HashMap<String, String>();
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
TestString ts = new TestString();
ts.vi.add(new IPSegment().Reset(1, 2, 3));
ts.vi.add(new IPSegment().Reset(2, 2, 4));
ts.vi.add(new IPSegment().Reset(3, 2, 5));
ts.vi.add(new IPSegment().Reset(4, 2, 6));
System.out.println(ts.vi.size());
System.out.println(ts.vi.get(2).ip_s + "\t" + ts.vi.get(2).ip_e + "\t" + ts.vi.get(2).p);
ts.hii.put(new IPSegment().Reset(2,2,3), 4);
ts.hii.put(new IPSegment().Reset(2,3,3), 7);
ts.hii.put(new IPSegment().Reset(3,2,3), 9);
System.out.println(ts.hii.size());
System.out.println(ts.hii.toString());
System.out.println((Integer)ts.hii.get(new IPSegment().Reset(2,3,3)));
System.out.println((Integer)ts.hii.get(new IPSegment().Reset(3,2,3)));
ts.hss.put("1", "hello");
System.out.println((String)ts.hss.get("1"));
}
}
线程池通俗的描述就是预先创建若干空闲线程，等到需要用多线程去处理事务的时候去唤醒某些空闲线程执行处理任务，这样就省去了频繁创建线程的时间，因为频 繁创建线程是要耗费大量的CPU资源的。如果一个应用程序需要频繁地处理大量并发事务，不断的创建销毁线程往往会大大地降低系统的效率� ......
