基于Java的简易计算器能够完成整数和小数的运算

import java.awt.BorderLayout; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.HashMap; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JTextField; /* * 该计算器比较简陋，很多功能没有实现 * */ public class Compute extends JFrame implements ActionListener{ private static final long serialVersionUID = 1L; private HashMap<String,Object> number ; private HashMap<String,Character> operator ; private JTextField result; private JButton num0,num1,num2,num3,num4,num5,num6, num7,num8,num9;//定义数字 private JButton point;//定义小数点 private JButton add,sub,mul,div,equ,clearScreen;//定义加减乘除和等于号 private JPanel pan; public Compute(){ init(); } private void init(){ initNewComponent(); addNumListener(); pan.setLayout(new GridLayout(4,4)); setTitle("计算器"); pan.add(num7); pan.add(num8); pan.add(num9); pan.add(add); pan.add(num4); pan.add(num5); pan.add(num6); pan.add(sub); pan.add(num1); pan.add(num2); pan.add(num3); pan.add(mul); pan.add(num0); pan.add(point); pan.add(equ); pan.add(div); point.addActionListener(this); add.addActionListener(this); sub.addActionListener(this); mul.addActionListener(this); div.addActionListener(this); equ.addActionListener(this); clearScreen.addActionListener(this); add(result,BorderLayout.NORTH); add(pan,BorderLayout.CENTER); add(clearScreen,BorderLayout.SOUTH); pack(); setLocation(300,200); setResizable(false); setVisible(true); setDefaultCloseOperation(EXIT_ON_CLOSE); } @Override public void actionPerformed(ActionEvent e) { if(e.getSource()==point){ StringBuffer buffer = new StringBuffer(); String temp = result.getText(); if("".equals(temp)){ return; }else{ for(int i=0; i<temp.length(); i++){ if(temp.charAt(i)=='.'){ return; } } } buffer.append(temp); buffer.append("."); result.setText(buffer.toString()); } if(e.getSource()==add){ operator.put("oper",'+'); if(!isEmpty()){ numberFirstFormat(); clearText(); } } if(e.getSource()==sub){ operator.put("oper",'-'); if(!isEmpty()){ numberFirstFormat(); clearText(); } } if(e.getSource()==mul){ operator.put("oper",'*'); if(!isEmpty()){ numberFirstFormat(); clearText(); } } if(e.getSource()==div){ operator.put("oper",'/'); if(!isEmpty()){ numberFirstFormat(); clearText(); } } if(e.getSource()==equ){ if(!isEmpty()&& null!=operator.get("oper")){ numberSecondFormat(); getResult(); } } if(e.getSource()==clearScreen){ clearText(); } } private void initNewComponent(){ number = new HashMap<String,Object>(); operator = new HashMap<String,Character>(); result = new JTextField(20); num0 = new JButton("0"); num1 = new JButton("1"); num2 = new JButton("2"); num3 = new JButton("3"); num4 = new JButton("4"); num5 = new JButton("5"); num6 = new JButton("6"); num7 = new JButton("7"); num8 = new JButton("8"); num9 = new JButton("9"); point = new JButton("."); add = new JButton("+"); sub = new JButton("-"); mul = new JButton("*"); div = new JButton("/"); equ = new JButton("="); clearScreen = new JButton("clear screen"); pan = new JPanel(); result.setEditable(false); } private void numberFirstFormat(){ String temp = result.getText(); for(int i=0; i<temp.length(); i++){ if( '.'== temp.charAt(i)){ number.put("first",Float.parseFloat(temp)); return; } } number.put("first",Integer.parseInt(temp)); } private void numberSecondFormat(){ String temp = result.getText(); for(int i=0; i<temp.length(); i++){ if( '.'== temp.charAt(i)){ number.put("second",Float.parseFloat(temp)); return; } } number.put("second",Integer.parseInt(temp)); } private void getResult(){ Object o1 = number.get("first"); Object o2 = number.get("second"); switch(operator.get("oper")){ case '+': { result.setText(new Envir(new AddCalcue()).calNum(o1,o2).toString()); break; } case '-': { result.setText(new Envir(new SubCalcue()).calNum(o1,o2).toString()); break; } case '*': { result.setText(new Envir(new MulCalcue()).calNum(o1,o2).toString()); break; } case '/': { result.setText(new Envir(new DivCalcue()).calNum(o1,o2).toString()); break; } } } private boolean isEmpty(){ return "".equals(result.getText()); } private void clearText(){ result.setText(""); } private void addNumListener(){ num0.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("0"); result.setText(buffer.toString()); } }); num1.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("1"); result.setText(buffer.toString()); } }); num2.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("2"); result.setText(buffer.toString()); } }); num3.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("3"); result.setText(buffer.toString()); } }); num4.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("4"); result.setText(buffer.toString()); } }); num5.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("5"); result.setText(buffer.toString()); } }); num6.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("6"); result.setText(buffer.toString()); } }); num7.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("7"); result.setText(buffer.toString()); } }); num8.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("8"); result.setText(buffer.toString()); } }); num9.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEvent e) { StringBuffer buffer = new StringBuffer(); String temp = result.getText(); buffer.append(temp); buffer.append("9"); result.setText(buffer.toString()); } }); } public static void main(String[] args) { new Compute(); } }