wiasliao
There is nothing special. This account is for my reports,homework.
Java程式碼範例
http://slides.com/wiasliao/deck-5#/
Hello World
class Main{
public static void main(String[] args){
System.out.println("Hello World");
}
}Data Type
class Main{
public static void main(String[] args){
int I = 4;
System.out.println(I);
float F = 4.0f;
System.out.println(F);
double D = 5.0;
System.out.println(D);
char C = 'C';
System.out.println(C);
String Str = "GREAT";
System.out.println(Str);
}
}輸入
import java.util.Scanner;
class Main {
public static void main(String[] argv){
//命名一個空間 scan 去存放 Scanner 物件
Scanner scan = new Scanner(System.in);
//1.取得數入的整數
int num = scan.nextInt();
System.out.println(num);
//2.取得輸入的浮點數
float flo = scan.nextFloat();
System.out.println(flo);
//3.取得輸入的浮點數
double dd = scan.nextDouble();
System.out.println(dd);
//4.取得字串
String str = scan.nextLine();
System.out.println(str);
}
}If
class Main {
public static void main(String[] argv){
int a = 3;
if(a==1){
System.out.println("Equal to one");
}else if(a==2){
System.out.println("Equal to two");
}else{
System.out.println("Equal to nothing");
}
}
}While
class Main {
public static void main(String[] argv) {
int counter = 10;
while(counter>0){
System.out.println(counter);
counter--;
}
}
}For
class Main {
public static void main(String[] argv) {
for(int i=0;i<10;i++){
System.out.println(i);
}
}
}Try Catch
class Main {
public static void main(String[] args) {
try {
System.out.println(1 / 0);
}
catch (ArithmeticException qqqq) {
System.out.println("算術錯誤的例外");
}
catch (Exception dddd) {
System.out.println("something wrong");
}
}
}類別class
class Main{
public static void main(String[] args){
//build a fish;
fish f1 = new fish("Jellyfish","White");
System.out.println(f1.Name);
System.out.println(f1.Color);
//movement
f1.swim();
}
public static class fish {
String Name = "";
String Color = "";
//Constructor
public fish(String Name, String Color){
this.Name = Name;
this.Color = Color;
}
//Function
public void swim(){
System.out.println("splaxh~");
}
}
}網路聊天室
- GUI
- 多執行緒
- 網路連線
GUI
import java.awt.*;
import java.awt.event.*;
import java.awt.Container;
import java.awt.Color;
import javax.swing.*;
public class Example2 extends JFrame{
JLabel Label = new JLabel("Click and plus one");
JButton Button = new JButton("+1");
JTextArea Area = new JTextArea("0");
JPanel p = new JPanel();
public static void main(String[] args) {
Example2 main = new Example2();
main.setSize(500,500);
main.setVisible(true);
main.setResizable(true);
main.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
main.setLocationRelativeTo(null);
}
Example2(){
super("GUI test");
p.setLayout(null);
//p.setBackground(Color.GRAY);
p.setOpaque(true);
Label.setBounds(20,20,200,20);
Button.setBounds(20,110,200,20);
Area.setBounds(20,50,30,20);
Container c = this.getContentPane();
c.add(Label);
c.add(Button);
c.add(Area);
c.add(p);
}
}多執
行緒
EX1: 找打手
EX2: 賽馬
class Main {
public static void main(String[] args) {
Worker w1 = new Worker();
w1.start();
System.out.println("Homework had been finished in main.");
}
public static class Worker extends Thread {
public void run(){
System.out.println("Homework had been finished in Thread.");
}
}
}class Main {
public static void main(String[] args) {
int h1 = 0;
Horse h2 = new Horse();
h2.start();
for(int i=0;i<100;i++){
h1++;
System.out.println("H1: "+h1);
}
}
public static class Horse extends Thread{
public void run(){
int h = 0;
for(int i=0;i<100;i++){
h++;
System.out.println("H2: "+h);
}
}
}
}網路
連線
import java.net.*;
class Main {
public static void main(String[] argv) {
String ip = "127.0.0.1";
int port = 3000;
//建立連線
Socket c1 = new Socket(ip,port);
}
}聊天室程式碼
有挖空要自己填坑喔(5個)
import java.io.*;
import java.net.*;
import java.awt.Color;
import java.awt.Container;
import java.awt.event.*;
import javax.swing.*;
public class Example2 extends JFrame implements ActionListener{
JLabel iplabel = new JLabel("IP：");
JTextArea ipArea = new JTextArea();
JLabel portlabel = new JLabel("Port：");
JTextArea portArea = new JTextArea();
JLabel useridlabel = new JLabel("暱稱：");
JTextArea userid = new JTextArea();
JButton connect = new JButton("連 線");
JLabel chatroomlabel = new JLabel("工資館營聊天室");
JTextArea chatroom = new JTextArea();
JLabel inputmessagelabel = new JLabel("輸入訊息：");
JTextArea inputmessage = new JTextArea();
JButton send = new JButton("傳 送");
JPanel p = new JPanel() ;
JScrollPane scroll;
Socket cl;
BufferedReader reader;
PrintStream writer;
String name="";
String ip="";
DataInputStream dis;
public static void main(String[] args) throws Exception {
Example2 main = new EXample2();
main.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
main.setSize(500,670);
main.setVisible(true);
main.setResizable(false);
main.setLocationRelativeTo(null);
}
Example2 (){
super("GUI Client");
p.setLayout(null) ;
p.setBackground(Color.GRAY);
p.setOpaque(true);
iplabel.setBounds(20, 20, 30, 20);
ipArea.setBounds(50, 20, 200, 20);
portlabel.setBounds(270, 20, 40, 20);
portArea.setBounds(320, 20, 150, 20);
useridlabel.setBounds(20, 50, 50, 20);
userid.setBounds(70, 50, 180, 20);
connect.setBounds(270, 50, 70, 20);
connect.setBackground(Color.white);
connect.setOpaque(true);
connect.addActionListener(this);
chatroomlabel.setBounds(20, 80, 100, 20);
scroll =new JScrollPane(chatroom);
scroll.setVerticalScrollBarPolicy(
JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
scroll.setVerticalScrollBarPolicy(
ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
scroll.setBounds(20, 100, 450, 400);
inputmessagelabel.setBounds(20,510,100,20);
inputmessage.setBounds(20,530,375,50);
send.setBounds(400, 530, 70, 50);
send.setBackground(Color.white);
send.setOpaque(true);
send.addActionListener(this);
Container c = this.getContentPane();
c.add(iplabel);
c.add(ipArea);
c.add(portlabel);
c.add(portArea);
c.add(useridlabel);
c.add(userid);
c.add(connect);
c.add(chatroomlabel);
//c.add(chatroom);
c.add(scroll);
c.add(inputmessagelabel);
c.add(inputmessage);
c.add(send);
c.add(p);
}
public class IncomingReader implements Runnable{
public void run(){
String message;
try{
while (true){
if((message = reader.readLine()) != null) {
chatroom.append(message+'\n');
}
else {
break;
}
}
scroll=new JScrollPane(chatroom);
}catch(Exception ex ){
ex.printStackTrace();
}
}
}
private void EstablishConnection(){
try{
//請求建立連線
ip=ipArea.getText();
String port=portArea.getText();
int i=Integer.parseInt(port);
cl = new Socket(ip,i);
InputStreamReader streamReader =
//取得Socket的輸入資料流
new InputStreamReader(cl.getInputStream());
//放入暫存區
reader = new BufferedReader(streamReader);
//取得Socket的輸出資料流
writer = new PrintStream(cl.getOutputStream());
}catch(Exception ex ){
ex.printStackTrace();
System.out.println("建立連線失敗");
}
}
public void actionPerformed(ActionEvent e){
String str=e.getActionCommand();
//按下設定
if(str.equals("連 線")){
ip = ipArea.getText();
EstablishConnection();
//建立接收資料執行緒----
Thread readerThread = new Thread(new IncomingReader());
readerThread.start();
//按下送出
}
else if(str.equals("傳 送")){
//不可沒有ip及送出空白
ip = ipArea.getText();
name=userid.getText();
if((ip!=null)&&(inputmessage.getText()!="")){
try{//送出資料
writer.println((name+":"+inputmessage.getText()));
//刷新該串流的緩衝。
writer.flush();
}catch(Exception ex ){
System.out.println("送出資料失敗");
}
//清完輸入欄位
inputmessage.setText("");
//按下送出
}
}
}
}Setting
- IP : 140.116.7.193
- Port : (一二三小) : 9999
- Port : (四五六小) : 8888
deck
By wiasliao
deck
- 302
