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import javax.swing.*;
import java.awt.BorderLayout;
import java.awt.Graphics;
import java.awt.event.*;
public class ThreadDemo extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
public ThreadDemo() {
JButton btn = new JButton("Click me");
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Thread thread1 = new Thread(new Runnable() {
public void run() {
Graphics g = getGraphics();
for (int i = 10; i < 300; i += 10) {
try {
Thread.sleep(100);
g.drawOval(i, 100, 10, 10);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
Thread thread2 = new Thread(new Runnable() {
public void run() {
Graphics g = getGraphics();
for (int i = 10; i < 300; i += 10) {
try {
Thread.sleep(500);
g.drawOval(i, 150, 15, 15);
g.draw3DRect(i, i, i, ......
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package com.wmmad.test;
import junit.framework.TestCase;
/**
* @author madding.lip
*
* <pre>
* class: compare the autoboxing and unboxing and normal's performance
* </pre>
*
*/
@SuppressWarnings("unused")
public class BoxTest extends TestCase {
public static void main(String[] args) {
testAutoboxing();
testUnboxing();
testChangeToObject();
testChangeToData();
testNormal();
testNormal1();
}
public static void testAutoboxing() {
long start = System.currentTimeMillis();
Integer result = 0;
for (int i = 0; i < 1000000000; i++) {
result = i; // autoboxing
}
long end = System.currentTimeMillis();
System.out.println("autoboxing use time is£º " + (end - start) + "ms");
}
public static void testUnboxing() {
int result = 0;
long start = System.currentTimeMilli ......
package homework01;
public class TestWhile {
public static double factorial(int n) //Çó½×³Ëº¯Êý
{
if(n==0) return 1;
else return n* factorial(n-1);
}
public static void main(String[] args) {
System.out.println(factorial(170));//test:ÄÜ´òÓ¡³öÀ´£¬170Ö®ºó±ã²»ÄÜ´òÓ¡ÁË
/*1¡¢Ê¹ÓÃwhileÑ»·¼ÆËã1-1000Ö®¼äÄܱ»3ºÍ7ͬʱÕû³ýµÄÕûÊýÖ®ºÍ*/
int count=0;//ÕûÊýÖ®ºÍ
int i=1000;
while(i>0){
if((i%3==0)&&(i%7==0)){
count+=i;
}
i--;
}
System.out.println("1-1000Ö®¼äÄܱ»3ºÍ7ͬʱÕû³ýµÄÕûÊýÖ®ºÍ:"+count);
/*2¡¢Ê¹ÓÃforÑ»·¼ÆËã8+88+888+···µÄǰ10ÏîÖ®ºÍ*/
long mun=0;
for(int j=0;j<10;j++){
mun+=mun+8*(Math.pow(10, j));
//System.out.println(mun); //test
}
System.out.println("8+88+888+···µÄǰ10ÏîÖ®ºÍ:"+mun);
/* 3¡¢¼ÆËã1-1/3+1/5-1/7+···µÄǰ10000ÏîÖ®ºÍ */
double mun2=0;
for(int n=0;n<10000;n++){
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