"Java GUI applications based on a realization" - this is the last semester December 20 large job Java programs, wanted to finish was sent to the blog, until now the results of a hair.
The big work I do is a calculator to do when it is found to be more complicated than I expected to start. Calculator is not so easy to do, ha ha, really easy to think of doing on the ignorant force.
We hope to give students learn, learn with it, I have a problem can be private.
The code is too long, you need the source code and executable files can Baidu network disk to receive:
Link: https: //pan.baidu.com/s/1KZr7PkqTpv922sCWyScs8g
extraction code: w434
Renderings:
Main Algorithm: receiving an expression on the graphical user interface input, the whole string cutting string as pass an array, an array of the array be infix expressions. (Parentheses) turn into postfix expression array using a comparison operator stack technology priority infix expression defining special string. Infix expression array, is necessary to remove the presence of parentheses operator to turn all the postfix expression parentheses operator, the postfix expression parentheses are not required, already present in the priority order. When the postfix expression obtained, using the same technology stack, the stack elements taken into calculation.
Interface layout: GUI-based graphical interface, visualization tools using WindowBuilder, be absolutely positioned layout modules. Components used to interface buttons, text boxes, input boxes, scrollable text fields, etc., are also provided bezel colors, font style and the like.
Summary: The big job to do calculator regarded as second attempt, also done before the web version of the calculator, but did not know infix expression, postfix and stack technology. It can be said is the core of these methods to complete the calculator. The calculator spent three nights to complete, and spent two nights were tested BUG, BUG is now basically does not exist. Accomplished in that the greatest difficulty calculator infix and postfix turn the two methods for calculating the outcome suffix expression. These two methods are the core code calculator lies. Computer comes without parentheses is standard calculator operator, but the function of cumulative calculation. The cumulative effect is not difficult to calculate, started doing when I made a cumulative calculation, and later added a brace to improve the operation removes cumulative. There bracket operation, the difficulty calculator is increased. Because in turn postfix infix expression, I need to determine priorities within and outside the brackets, after not able to compare incoming bracket operator within a postfix expression, because postfix expression does not need parentheses. Compared with the computer comes with a standard calculator, standard calculator is actually part of two expressions show, in part, display input, is part of the overall expression, and I only had a show that expression, so when the operator input values and there are some limitations. For example: You can not directly enter a negative number, you must enter a minus zero value. For the standard user input, I do a lot of input constraints. For example: There are two or more can not be connected to the operator, not the value of the decimal point and the point, right bracket must be the same number of left bracket and the like, these are written in the code logic, thereby giving the user a better experience a sense, but also to prevent misuse of the incoming data. Of course, if the operator end users multiplication and division addition and subtraction expressions press is equal to, or the lack of a right parenthesis is all right, it will not be affected. Overall this calculator to do the harvest is great.
Class has:
Calculator class: the GUI graphical interface implementation class, to achieve the overall layout of the calculator, and the call returns the contents StackToCalculator class. Wherein the monitoring function comprises achieve inner class ButtonHandler, and a method (doInit ()) initializing.
StackToCalculator categories: main algorithm calculator implementation class. Wherein the method comprises an array of strings revolutions (toArr (String text)), postfix infix expression transfer method (ToSuffix (String [] textArray) ), the method determines whether the value of (isNum (char strNum), isNum (String strNum)), operator priority comparison method (ToCampare (String str1)) and a final stack suffix calculation method of expressions (ToCacultor (String Ctext)).
On the code:
package work7;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.border.EmptyBorder;
import javax.swing.JTextArea;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.JLabel;
/**
* @author YoungIT
* @version 2019年12月18日 下午11:12:14
* @tips 计算器
*/
public class Cacultor extends JFrame {
private JPanel contentPane;
private JTextArea textArea;
private JButton btnNewButton,btnNewButton_1,btnNewButton_2,btnNewButton_3,
btnNewButton_4,btnNewButton_5,btnNewButton_6,btnNewButton_7,button,button_1,
button_2,button_3,button_4,button_5,button_6,button_7,
button_8,button_9,button_10,button_11,button_12;
private String textA = "";
private String cString = "";
private JTextField textField;
private int count = 0;//"+-x/"
private int cleft = 0;//标记 "("
private int cright = 0;//标记 ")"
private int point = 0;//标记 "."
private int cnum = 0;//标记 数字
private int flag = 0;//1-数字，2-运算符，3-点，4-左括，5-右括
private int fsum = 0;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Cacultor frame = new Cacultor();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public Cacultor() {
super("超智能计算器");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(700, 500, 620, 430);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
contentPane.setLayout(null);
setContentPane(contentPane);
btnNewButton = new JButton("C");
btnNewButton.setBounds(10, 78, 83, 44);
contentPane.add(btnNewButton);
btnNewButton_1 = new JButton(".");
btnNewButton_1.setBounds(92, 78, 83, 44);
contentPane.add(btnNewButton_1);
btnNewButton_3 = new JButton("BackSace");
btnNewButton_3.setBounds(174, 78, 200, 44);
contentPane.add(btnNewButton_3);
btnNewButton_4 = new JButton("7");
btnNewButton_4.setBounds(10, 129, 83, 44);
contentPane.add(btnNewButton_4);
btnNewButton_5 = new JButton("8");
btnNewButton_5.setBounds(92, 129, 83, 44);
contentPane.add(btnNewButton_5);
btnNewButton_6 = new JButton("9");
btnNewButton_6.setBounds(174, 129, 83, 44);
contentPane.add(btnNewButton_6);
btnNewButton_7 = new JButton("+");
btnNewButton_7.setBounds(256, 129, 118, 44);
contentPane.add(btnNewButton_7);
button = new JButton("4");
button.setBounds(10, 182, 83, 44);
contentPane.add(button);
button_1 = new JButton("5");
button_1.setBounds(92, 182, 83, 44);
contentPane.add(button_1);
button_2 = new JButton("6");
button_2.setBounds(174, 182, 83, 44);
contentPane.add(button_2);
button_3 = new JButton("1");
button_3.setBounds(10, 236, 83, 44);
contentPane.add(button_3);
button_4 = new JButton("2");
button_4.setBounds(92, 236, 83, 44);
contentPane.add(button_4);
button_5 = new JButton("3");
button_5.setBounds(174, 236, 83, 44);
contentPane.add(button_5);
button_6 = new JButton("(");
button_6.setBounds(10, 288, 83, 44);
contentPane.add(button_6);
button_7 = new JButton("0");
button_7.setBounds(92, 288, 83, 44);
contentPane.add(button_7);
button_8 = new JButton(")");
button_8.setBounds(174, 288, 83, 44);
contentPane.add(button_8);
button_9 = new JButton("-");
button_9.setBounds(256, 182, 118, 44);
contentPane.add(button_9);
button_10 = new JButton("x");
button_10.setBounds(256, 236, 118, 44);
contentPane.add(button_10);
button_11 = new JButton("/");
button_11.setBounds(256, 288, 118, 44);
contentPane.add(button_11);
button_12 = new JButton("=");
button_12.setBounds(10, 337, 364, 44);
contentPane.add(button_12);
textField = new JTextField();
textField.setBounds(10, 10, 364, 44);
textField.setEditable(false);
textField.setFont(new Font("华文彩云",Font.BOLD, 18));
textField.setHorizontalAlignment(JTextField.RIGHT);
contentPane.add(textField);
textField.setColumns(10);
JLabel lblByYoungit = new JLabel("by: YoungIT");
lblByYoungit.setBounds(309, 56, 75, 22);
contentPane.add(lblByYoungit);
textArea = new JTextArea();
textArea.setBounds(380, 10, 194, 371);
textArea.setEditable(false);
textArea.setLineWrap(true);
textArea.setFont(new Font("华文彩云",Font.BOLD, 18));
Color b = new Color(194,214,233);
Color c = new Color(238,238,238);
textArea.setBackground(c);
textArea.setBorder(BorderFactory.createMatteBorder(2,2,2,2,b));
JScrollPane scrollpane = new JScrollPane(textArea);
// scrollpane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
scrollpane.setBounds(384, 10, 210, 371);
contentPane.add(scrollpane);
ButtonHandler handler = new ButtonHandler();
button.addActionListener(handler);
button_1.addActionListener(handler);
button_2.addActionListener(handler);
button_3.addActionListener(handler);
button_4.addActionListener(handler);
button_5.addActionListener(handler);
button_6.addActionListener(handler);
button_7.addActionListener(handler);
button_8.addActionListener(handler);
button_9.addActionListener(handler);
button_10.addActionListener(handler);
button_11.addActionListener(handler);
button_12.addActionListener(handler);
btnNewButton.addActionListener(handler);
btnNewButton_1.addActionListener(handler);
btnNewButton_3.addActionListener(handler);
btnNewButton_4.addActionListener(handler);
btnNewButton_5.addActionListener(handler);
btnNewButton_6.addActionListener(handler);
btnNewButton_7.addActionListener(handler);
}
public void doInit() {
textA = "";
textField.setText(textA);
count = 0;//"+-x/"
cleft = 0;//标记 "("
cright = 0;//标记 ")"
point = 0;//标记 "."
cnum = 0;//标记 数字
flag = 0;
fsum = 0;
}
private class ButtonHandler implements ActionListener{
@Override
public void actionPerformed(ActionEvent e) {
String Ename = e.getActionCommand();
switch (Ename) {
case "C":
doInit();
break;
case "BackSace":
if(fsum==1) {
doInit();
}
try {
if(textA.length()>0) {
String laString = textA.substring(textA.length() - 1);
if(laString.equals(")")) {
cleft++;
}else if(laString.equals("0")) {
cnum = 0;
}
textA = textA.isEmpty()?"":textA.substring(0,textA.length() - 1);
textField.setText(textA);
char c = textA.charAt(textA.length()-1);
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
flag = 1;break;
case '+':
case '-':
case 'x':
case '/':
flag = 2;break;
case '.':
flag = 3;break;
case '(':
flag = 4;break;
case ')':
flag = 5;
break;
default:
break;
}
}
}catch (Exception e2) {
System.err.println("不要再删啦~已无内容！");
}
break;
case "0":
if(fsum==1) {
doInit();
}
if(flag == 2 || flag == 0){//1-数字，2-运算符，3-点，4-左括，5-右括
cnum = 1;
textA = textA + Ename;
textField.setText(textA);
flag = 1;
}else if(flag == 1 || flag == 3|| flag == 4) {
textA = textA + Ename;
textField.setText(textA);
flag = 1;
}
break;
case "1":
case "2":
case "3":
case "4":
case "5":
case "6":
case "7":
case "8":
case "9"://右括) 后不能输数字
if(fsum==1) {
doInit();
}
if(flag != 5&&cnum == 0){//1-数字，2-运算符，3-点，4-左括，5-右括
textA = textA + Ename;
textField.setText(textA);
flag = 1;
}
break;
case "+":
case "-":
case "x":
case "/"://不能输入:空,(,.,运算符
if(fsum==1) {
doInit();
break;
}
if(flag == 1||flag == 5){//0-空，1-数字，2-运算符，3-点，4-左括，5-右括
textA = textA + Ename;
// count = 1;//+-x/
point = 0;
cnum = 0;
textField.setText(textA);
flag = 2;
}
break;
case "."://前面只能是数字
if(fsum==1) {
doInit();
break;
}
if(flag == 1&&point == 0) {
textA = textA + Ename;
point = 1;//标记.
textField.setText(textA);
cnum = 0;
flag = 3;
}
break;
case "("://不能输入:(,),.,数字
if(fsum==1) {
doInit();
}
if(flag == 0 || flag == 2) {//空 运算符
textA = textA + Ename;
cleft++;
// cright = 0;
textField.setText(textA);
flag = 4;
}
System.out.println("cleft:"+cleft);
break;
case ")"://不能输入:(,.,运算符,空
if(fsum==1) {
doInit();
break;
}
if(((flag == 1 || flag == 4) && cleft > 0)||(flag == 5 && cleft > 0)) {//数字 右括号
textA = textA + Ename;
// cright = 0;
cleft--;
textField.setText(textA);
flag = 5;
}
System.out.println("cleft2:"+cleft);
break;
case "=":
if(fsum==1) {
doInit();
break;
}
try {
System.out.println("****************************");
System.out.println("输入的表达式："+textA);
StackToCacultor stackToCacultor = new StackToCacultor();
String lastStr = String.valueOf(textA.charAt(textA.length()-1));
if(!stackToCacultor.isNum(lastStr)&&!lastStr.equals(")")) {//删去最后位是运算符
textA = textA.isEmpty()?"":textA.substring(0, textA.length() - 1);
}
int i = 0,ckey = 0;
char c;
while (i<textA.length()) {//为了补上")"
c = textA.charAt(i);
if(c=='(') {
ckey++;
}else if(c==')') {
ckey--;
}
i++;
}
if(ckey > 0) {
for(int j=0;j<ckey;j++) {
textA = textA+")";
}
}
System.out.println("传入计算的表达式："+textA);
cString += textA;
String text2 = String.valueOf(stackToCacultor.ToCacultor(textA));
textField.setText(text2);
cString += " = "+text2 + '\n'+"******************"+ '\n';
textArea.setText(cString);
textA = text2;
fsum = 1;
}catch (Exception e2) {
System.err.println("请输入！");
}
break;
default:
break;
}
}
}
}
package work7;
import java.util.Stack;
import java.util.Vector;
/**
* @author YoungIT
* @version 2019年12月18日 下午1:01:18
* @tips 使用堆栈计算
*/
public class StackToCacultor{
private static String[] textArr = new String[50];
private static String[] textArr2 = new String[50];
private final static int sizeofSum = 2;//优先级
private final static int sizeofSub = 2;
private final static int sizeofMul = 3;
private final static int sizeofDiv = 3;
private final static int sizeofLbra = 1;
private final static int sizeofRbra = 0;
public StackToCacultor() {
for(int i = 0; i<textArr.length; i++) {
textArr[i] = null;
textArr2[i] = null;
}
}
//最终计算
public static double ToCacultor(String Ctext) {
int numkey = 0;
int strkey = 0;
String[] strArr = ToSuffix(toArr(Ctext));
Stack<String> stack = new Stack<String>();
double sum = 0;
try {
for(int i=0;i<strArr.length-1;i++) {
numkey = 0;
strkey = 0;
if(strArr[i]==null) {
while(!stack.isEmpty()) {
String top = stack.pop();
if(isNum(top)) {
sum = Double.parseDouble(top);//*********//
}
}
break;
} // 2x(3+2)
System.out.println("ToCacultor-后缀:"+strArr[i]);
if(stack.empty()) {
stack.push(strArr[i]);
}else {
for (String x : stack) {
if(isNum(x)) {
numkey++;
}else {
strkey++;
}
}
if(isNum(strArr[i])) {
if(numkey==1&&strkey==1) {
String str = stack.pop();
double num3 = Double.parseDouble(stack.pop());
double s2 = Double.parseDouble(strArr[i]);
double sum2 = 0;
switch (str) {
case "+":
sum2 = num3 + s2;
break;
case "-":
sum2 = num3 - s2;
break;
case "x":
sum2 = num3 * s2;
break;
case "/":
sum2 = num3 / s2;
break;
}
stack.push(String.valueOf(sum2));
}else {
stack.push(String.valueOf(strArr[i]));
}
}else {
if(numkey>=2) {
double num1 = Double.parseDouble(stack.pop());
double num2 = Double.parseDouble(stack.pop());
double s = 0;
switch (strArr[i]) {
case "+":
s = num2 + num1;
break;
case "-":
s = num2 - num1;
break;
case "x":
s = num2 * num1;
break;
case "/":
s = num2 / num1;
break;
}
stack.push(String.valueOf(s));
}else {
stack.push(String.valueOf(strArr[i]));
}
}
}
}
}catch (Exception e) {
System.err.println("计算出错！请重启~");
}
System.out.println("计算结果："+sum);
return sum;
}
//字符转数组
public static String[] toArr(String text) {
int i = 0,j = 0;
char c;
while (i<text.length()) {
c = text.charAt(i);
if(c=='('||c==')'||c =='+'||c =='-'||c =='x'||c =='/') {
textArr[j++] = String.valueOf(c);
i++;
}else {// 数字
String num = "";
while (true) {
if(i>=text.length()) {
break;
}
c = text.charAt(i);
if(c==')'||c =='+'||c =='-'||c =='x'||c =='/') {
break;
}
num += c;
i++;
}
textArr[j++] = num;
}
}
return textArr;
}
//中缀表达式 转 后缀
public static String[] ToSuffix(String[] textArray) {
int k=0;
Stack stack = new Stack();
for(int i=0;i<textArray.length-1;i++) {
if(textArray[i]!=null) {
System.out.println("ToSuffix中缀:"+textArray[i]);
int priority = ToCampare(textArray[i]); //2x(3+2)
if(isNum(textArray[i])) {//读取到数字
textArr2[k++] = textArray[i];
}else {
if(!stack.empty()) {
if(textArray[i].equals("(")) {
stack.push(textArray[i]);
continue;
}else if(textArray[i].equals(")")){
System.out.println(String.valueOf(stack.peek()));
while (!String.valueOf(stack.peek()).equals("(")) {
textArr2[k++] = String.valueOf(stack.pop());
}
stack.pop();
continue;
}else if(priority>ToCampare(String.valueOf(stack.peek()))) {//优先级大于 栈顶
stack.push(textArray[i]);
continue;
}else {
while (priority<=ToCampare(String.valueOf(stack.peek()))) {
textArr2[k++] = String.valueOf(stack.pop());
if(stack.isEmpty()) {
break;
}
}
stack.push(textArray[i]);
continue;
}
}else {
stack.push(textArray[i]);
}
}
}else {
while (!stack.empty()) {
textArr2[k++] = String.valueOf(stack.pop());
}
}
}//for
return textArr2;
}
//是否为数1
public static boolean isNum(char strNum) {
if(strNum=='1'||strNum=='2'||strNum=='3'||strNum=='4'
||strNum=='5'||strNum=='6'||strNum=='7'
||strNum=='8'||strNum=='9'||strNum=='0') {
return true;
}else {
return false;
}
}
//是否为数2
public static boolean isNum(String strNum) {
if(!strNum.equals("+")&&!strNum.equals("-")&&!strNum.equals("x")
&&!strNum.equals("/")&&!strNum.equals("(")&&!strNum.equals(")")) {
return true;
}else {
return false;
}
}
//运算符优先级比较 str1>str2 返回true
public static int ToCampare(String str1) {
int key = -1;
switch (str1) {
case "(":
key = 1;
break;
case ")":
key = 0;
break;
case "+":
case "-":
key = 2;
break;
case "x":
case "/":
key = 3;
break;
}
return key;
}
//test
public static void main(String[] args) {
// String[] strings = toArr("(1222.2x231+232)/123123.23+(323.2+323)");
// String[] strings = toArr("2x(3+2)");//10
// String[] strings = toArr("1+1");
// for(int i=0;i<strings.length-1;i++) {
// if(strings[i]!=null) {
// System.out.println(strings[i]);
// }
// }
// System.out.println(" ");
// ToSuffix(strings);
// for(int i=0;i<textArr2.length-1;i++) {
// if(textArr2[i]!=null) {
// System.out.println(textArr2[i]);
// }
// }
// System.out.println(ToCacultor("2x(3+2)"));
// System.out.println(ToCacultor("1+1"));
}
}
The code is too long, you need the source code and executable files can Baidu network disk to receive:
Link: https: //pan.baidu.com/s/1KZr7PkqTpv922sCWyScs8g
extraction code: w434
Learn, progress together ~
