如何编写一个Java小程序通过java -jar的方式去测试一个功能

整个项目打包到现场部署需要大量成本的时候，编写一个单功能的测试小程序部署就会便捷很多。 直接上教程

注意：如果需要引入的第三方包是多个，在Windows中用分号;隔开，在Linux中用冒号:隔开

(1) import javaxswingJFrame;

import javaxswingJOptionPane;

public class HelloWorld {

public static void main(String args[]){

JFrame ff=new JFrame();

String R=JOptionPaneshowInputDialog("请输入圆的半径:");

double r=DoubleparseDouble(R);

JOptionPaneshowMessageDialog(ff, "圆的面积为："+314rr+"\n"+"圆的周长为："+2314r);

}

}

(2) import javautilScanner;

public class HelloWorld {

public static void main(String args[]){

Scanner scan=new Scanner(Systemin);

int a=scannextInt();

int b=scannextInt();

int c=scannextInt();

if(a+b>c&&b+c>a&&a+c>b){

if((aa==bb+cc)||(cc==aa+bb)||(bb==aa+cc))

Systemoutprint("是直角三角形");

}else

Systemoutprint("不能构成三角形");

}

}

(3) public static void main(String args[]){

int a=1000,i=0,sum=0;

while(i<=a)

{

if(i%2==0)

sum=sum+i;

i++;

}

Systemoutprint(sum);

}

(4) public static void main(String args[]){

int a=12454,i=0;

while(a>0){

a=a/10;

i++;

}

Systemoutprintln(i);

}

(5) import javautilScanner;

public class HelloWorld {

public static void main(String args[]){

Scanner scan=new Scanner(Systemin);

int road=scannextInt();

int weight=scannextInt();

double sum=0;

if (road<=100){

sum=weightroad1;

}else if(road<=300){

sum=weightroad09;

}else if(road<=500){

sum=weightroad08;

}else if(road<=1000){

sum=weightroad07;

}else

sum=weightroad06;

Systemoutprint(sum);

}

}

(6) public static void main(String args[]){

int sum=0;

int total=1;

for(int i=1;i<=4;i++){

for(int j=1;j<=i;j++)

total=totalj;

sum=sum+total;

total=1;

}

Systemoutprintln(sum);

}

参考下，建议自己动手，进步更快哦

package com;

public interface PlaneGraphics {

public abstract double area();

public abstract double perimeter();

public abstract void print();

}

package com;

public class Rectangle implements PlaneGraphics{

private double x = 75;

private double y = 157;

private double s = 0;

private double l= 0;

public double area() {

s = x y;

return s;

}

public double perimeter() {

l = 2 (x + y);

return l;

}

public void print() {

Systemoutprintln("这是长方形");

Systemoutprintln("长方形的宽度："+x+"长方形的长度："+y);

Systemoutprintln("长方形的面积："+s);

Systemoutprintln("长方形的周长："+l);

}

package com;

public class Ellipse implements PlaneGraphics {

private double a = 57;

private double b = 25;

private double s = 0;

private double l = 0;

private double pie = 314;

public double area() {

s = pie a b;

return s;

}

public double perimeter() {

double m = 0;

m = javalangMathsqrt(a b);

l = pie (15 (a+b) - m);

return l;

}

public void print() {

Systemoutprintln("这是椭圆形");

Systemoutprintln("椭圆形的a轴长："+a+"椭圆形的b轴长："+b);

Systemoutprintln("椭圆形的面积："+s);

Systemoutprintln("椭圆形的周长："+l);

}

}

package com;

public class Test {

public static void main(String[] args) {

Rectangle rec = new Rectangle();

recarea();

recperimeter();

recprint();

Ellipse ell = new Ellipse();

ellarea();

ellperimeter();

ellprint();

}

}

import javaxswing;

import javaawt;

import javaawtevent;

public class Calculator extends JFrame implements ActionListener{

private static final long serialVersionUID = 8199443193151152362L;

private JButton bto_s=new JButton("sqrt"),bto_zf=new JButton("+/-"),bto_ce=new JButton("CE"),bto_c=new JButton("C"),bto_7=new JButton("7"),

bto_8=new JButton("8"),bto_9=new JButton("9"),bto_chu=new JButton("/"),bto_4=new JButton("4"),bto_5=new JButton("5"),

bto_6=new JButton("6"),bto_cheng=new JButton(""),bto_1=new JButton("1"),bto_2=new JButton("2"),bto_3=new JButton("3"),

bto_jian=new JButton("-"),bto_0=new JButton("0"),bto_dian=new JButton(""),bto_deng=new JButton("="),bto_jia=new JButton("+");

JButton button[]={bto_s,bto_zf,bto_ce,bto_c,bto_7,bto_8,bto_9,bto_chu,bto_4,bto_5,bto_6,bto_cheng,bto_1,bto_2,bto_3,bto_jian,

bto_0,bto_dian,bto_deng,bto_jia};

private JTextField text_double;// = new JTextField("0");

private String operator = "="; //当前运算的运算符

private boolean firstDigit = true; // 标志用户按的是否是整个表达式的第一个数字,或者是运算符后的第一个数字

private double resultNum = 00; // 计算的中间结果

private boolean operateValidFlag = true; //判断 *** 作是否合法

public Calculator()

{

super("Calculator");

thissetBounds(300, 300, 300, 300);

thissetResizable(false);

thissetBackground(Colororange);

thissetDefaultCloseOperation(EXIT_ON_CLOSE);

thisgetContentPane()setLayout(new BorderLayout());//设置布局

text_double=new JTextField("0",20);//设置文本区

text_doublesetHorizontalAlignment(JTextFieldRIGHT);//设置水平对齐方式未右对齐

thisgetContentPane()add(text_double,BorderLayoutNORTH);//将文本区添加到Content北部

JPanel panel=new JPanel(new GridLayout(5,4));//在内容窗口添加一个网格布局

thisgetContentPane()add(panel);//添加panel面板

for(int i=0;i<buttonlength;i++)//在面板上添加按钮

paneladd(button[i]);

for(int i=0;i<buttonlength;i++)

button[i]addActionListener(this);//为按钮注册

text_doublesetEditable(false);//文本框不可编辑

text_doubleaddActionListener(this);//

thissetVisible(true);

}

public void actionPerformed(ActionEvent e)//

{

String c= egetActionCommand();//返回与此动作相关的命令字符串。

Systemoutprintln("##########command is "+c);

if(cequals("C")){

handleC(); //用户按了“C”键

}

else if (cequals("CE")) // 用户按了"CE"键

{

text_doublesetText("0");

}

else if ("0123456789"indexOf(c) >= 0) // 用户按了数字键或者小数点键

{

handleNumber(c); // handlezero(zero);

} else //用户按了运算符键

{

handleOperator(c);

}

}

private void handleC() // 初始化计算器的各种值

{

text_doublesetText("0");

firstDigit = true;

operator = "=";

}

private void handleNumber(String button) {

if (firstDigit)//输入的第一个数字

{

text_doublesetText(button);

} else if ((buttonequals("")) && (text_doublegetText()indexOf("") < 0))//输入的是小数点，并且之前没有小数点，则将小数点附在结果文本框的后面

//如果字符串参数作为一个子字符串在此对象中出现，则返回第一个这种子字符串的第一个字符的索引；如果它不作为一个子字符串出现，则返回 -1

{

text_doublesetText(text_doublegetText() + "");

} else if (!buttonequals(""))// 如果输入的不是小数点，则将数字附在结果文本框的后面

{

text_doublesetText(text_doublegetText() + button);

}

// 以后输入的肯定不是第一个数字了

firstDigit = false;

}

private void handleOperator(String button) {

if (operatorequals("/")) {

// 除法运算

// 如果当前结果文本框中的值等于0

if (getNumberFromText() == 00){

// *** 作不合法

operateValidFlag = false;

text_doublesetText("除数不能为零");

} else {

resultNum /= getNumberFromText();

}

} else if (operatorequals("+")){

// 加法运算

resultNum += getNumberFromText();

} else if (operatorequals("-")){

// 减法运算

resultNum -= getNumberFromText();

} else if (operatorequals("")){

// 乘法运算

resultNum = getNumberFromText();

} else if (operatorequals("sqrt")) {

// 平方根运算

if(getNumberFromText()<0){

operateValidFlag = false;

text_doublesetText("被开方数不能为负数");}

else

resultNum = Mathsqrt(resultNum);

}

else if (operatorequals("+/-")){

// 正数负数运算

resultNum = resultNum (-1);

} else if (operatorequals("=")){

// 赋值运算

resultNum = getNumberFromText();

}

if (operateValidFlag) {

// 双精度浮点数的运算

long t1;

double t2;

t1 = (long) resultNum;

t2 = resultNum - t1;

if (t2 == 0) {

text_doublesetText(StringvalueOf(t1));

} else {

text_doublesetText(StringvalueOf(resultNum));

}

}

operator = button; //运算符等于用户按的按钮

firstDigit = true;

operateValidFlag = true;

}

private double getNumberFromText() //从结果的文本框获取数字

{

double result = 0;

try {

result = DoublevalueOf(text_doublegetText())doubleValue(); // ValueOf()返回表示指定的 double 值的 Double 实例

} catch (NumberFormatException e){

}

return result;

}

public static void main(final String[] args) {

new Calculator();

}

}

给你一个简单的实现吧，注意一定要先运行MyServerjava

//MyCilentjava

import javaio;

import javanet;

import javaxswing;

import javaawt;

import javaawtevent;

public class MyClient extends JFrame implements ActionListener{

JTextField tf;

JTextArea tx;

JButton bt;

PrintWriter out;

public MyClient(){

tf=new JTextField(20);

tx=new JTextArea();

txsetLineWrap(true);

txsetWrapStyleWord(true);

JPanel pan=new JPanel();

JScrollPane jsp=new JScrollPane(tx);

add(jsp,"Center");

bt=new JButton("SEND");

btaddActionListener(this);

panadd(tf);

panadd(bt);

add(pan,"South");

thisaddWindowListener(new WindowAdapter(){

public void windowClosing(WindowEvent e){

Systemexit(0);

}

});

setTitle("THE CLIENT");

setSize(400,300);

setVisible(true);

try{

Socket socket=new Socket("127001",1680);

out=new PrintWriter(socketgetOutputStream(),true);

InputStreamReader in = new InputStreamReader(socketgetInputStream());

BufferedReader sin=new BufferedReader(in);

String s;

while(true){

s=sinreadLine();

txappend("#Server Said#: "+s+"\n");

}

}catch(Exception e){

eprintStackTrace();

}

}

public void actionPerformed(ActionEvent e){

if(egetSource()==bt){

txappend("@Client Said@: "+tfgetText()+"\n");

outprintln(tfgetText());

tfsetText("");

}

}

public static void main(String[] args){

MyClient mct = new MyClient();

}

}

//MyServerjava

import javaio;

import javanet;

import javaxswing;

import javaawt;

import javaawtevent;

public class MyServer extends JFrame implements ActionListener{

JTextField tf;

JTextArea tx;

JButton bt;

JScrollPane jsp;

JPanel pan;

PrintWriter out;

public MyServer(){

tx=new JTextArea();

txsetLineWrap(true);

txsetWrapStyleWord(true);

jsp=new JScrollPane(tx);

tf=new JTextField(20);

bt=new JButton("SEND");

btaddActionListener(this);

pan=new JPanel();

panadd(tf);

panadd(bt);

add(pan,"South");

add(jsp,"Center");

thisaddWindowListener(new WindowAdapter(){

public void windowClosing(WindowEvent e){

Systemexit(0);

}

});

setTitle("THE SERVER");

setSize(400,300);

setVisible(true);

try{

ServerSocket server = new ServerSocket(1680);

Socket socket = serveraccept();

InputStreamReader in = new InputStreamReader(socketgetInputStream());

BufferedReader sin=new BufferedReader(in);

out=new PrintWriter(socketgetOutputStream(),true);

while(true){

String s=sinreadLine();

txappend("@Client Said@: "+s+"\n");

}

}catch(Exception e){

eprintStackTrace();

}

}

public void actionPerformed(ActionEvent e){

if(egetSource()==bt){

String st = tfgetText();

txappend("#Server Said#: "+st+"\n");

outprintln(st);

tfsetText("");

}

}

public static void main(String[] args){

MyServer msr = new MyServer();

}

}

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