package triangleDemo;
public class Triangle{public String triangle(int a,int b,int c){String result;if ((a>=1&&a<=100)&&(b>=1&&b<=100)&&(c>=1&&c<=100)) {if ((a+b>c)&&(a+c>b)&&(b+c>a)) {if (a*a+b*b==c*c||a*a+c*c==b*b||b*b+c*c==a*a) {result="直角三角形.";} else if (a==b&&b==c&&a==c) {result="等边三角形.";} else if (a==b||a==c||b==c) {result="等腰三角形.";} else {result="一般三角形.";}} else {result="不能构成三角形.";}} else {result="边的值不在范围内！";}return result;}public boolean Validation(String[] value){if(value.length<3){//没有三个数据return false;}try {for(int i=0;i<3;i++){int b = Integer.valueOf(value[i]).intValue();}} catch (NumberFormatException e){//不能转换成整型return false;}return true;}public int perimeter(int a,int b,int c){return a+b+c;}public float triangleArea(int a,int b,int c){float s = (float) (0.5*perimeter( a, b, c));return (float) Math.sqrt((s*(s-a)*(s-b)*(s-c)));}
}

package triangleDemo;import java.awt.EventQueue;
import java.awt.Font;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JTextField;import triangleDemo.Triangle;public class DisTriangle{private JFrame frame;private final JLabel label = new JLabel("请输入三角形的三条边：");private final JLabel lblA = new JLabel("a：");private final JLabel lblB = new JLabel("b:");private final JLabel lblC = new JLabel("c:");private final JLabel result_1 = new JLabel("这个三角形是：");private final JLabel result_2 = new JLabel("面积是：       周长是：");private final JTextField lengthOfa = new JTextField();private final JTextField lengthOfb = new JTextField();private final JTextField lengthOfc = new JTextField();private final JButton calculate = new JButton("确定");private final JButton clean = new JButton("清空");private Triangle tri;/*** Launch the application.*/public static void main(String[] args) {EventQueue.invokeLater(new Runnable() {public void run() {try {new DisTriangle();} catch (Exception e) {e.printStackTrace();}}});}/*** Create the frame.* @wbp.parser.entryPoint*/public DisTriangle() {frame = new JFrame("三角形计算程序");frame.setBounds((Toolkit.getDefaultToolkit().getScreenSize().width/2)-256, (Toolkit.getDefaultToolkit().getScreenSize().height/2)-192, 450, 360);frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);frame.getContentPane().setLayout(null);frame.setVisible(true);frame.setResizable(false);label.setFont(new Font("宋体", Font.PLAIN, 16));label.setBounds(24, 10, 350, 30);frame.getContentPane().add(label);result_1.setFont(new Font("宋体", Font.PLAIN, 16));result_1.setBounds(24, 192, 350, 30);frame.getContentPane().add(result_1);result_2.setFont(new Font("宋体", Font.PLAIN, 16));result_2.setBounds(24, 254, 350, 30);frame.getContentPane().add(result_2);lblA.setFont(new Font("宋体", Font.PLAIN, 16));lblA.setBounds(60, 70, 30, 15);lblB.setFont(new Font("宋体", Font.PLAIN, 16));lblB.setBounds(175, 70, 30, 15);lblC.setFont(new Font("宋体", Font.PLAIN, 16));lblC.setBounds(295, 70, 30, 15);frame.getContentPane().add(lblA);frame.getContentPane().add(lblB);frame.getContentPane().add(lblC);lengthOfa.setBounds(89, 67, 70, 25);lengthOfb.setBounds(205, 65, 70, 25);lengthOfc.setBounds(315, 65, 70, 25);lengthOfa.setColumns(10);      lengthOfb.setColumns(10);lengthOfc.setColumns(10);frame.getContentPane().add(lengthOfa);frame.getContentPane().add(lengthOfb);frame.getContentPane().add(lengthOfc);calculate.setBounds(110, 130, 95, 25);frame.getContentPane().add(calculate);clean.setBounds(240, 130, 95, 25);frame.getContentPane().add(clean);calculate.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent arg0){if(arg0.getSource()==calculate){tri = new Triangle();String[] value = new String[3];value[0] = lengthOfa.getText();value[1] = lengthOfb.getText();value[2] = lengthOfc.getText();if(!tri.Validation(value)){//调用验证函数JOptionPane.showMessageDialog(null, "请确保输入的边为整数！", "错误", JOptionPane.ERROR_MESSAGE);allClean();}else{int a = Integer.valueOf(value[0]).intValue();//已验证过不再进行异常处理int b = Integer.valueOf(value[1]).intValue();int c = Integer.valueOf(value[2]).intValue();String triangleType = tri.triangle(a,b,c);result_1.setText("这个三角形是："+triangleType);if(triangleType.equals("边的值不在范围内！")){JOptionPane.showMessageDialog(null, "边的值不在范围内！", "错误", JOptionPane.ERROR_MESSAGE);allClean();}else if(triangleType.equals("不能构成三角形.")){JOptionPane.showMessageDialog(null, "不能构成三角形.", "错误", JOptionPane.ERROR_MESSAGE);allClean();}else{result_2.setText("面积是："+tri.triangleArea(a, b, c)+"     周长是："+tri.perimeter(a, b, c));}}}}});clean.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent arg0){if(arg0.getSource()==clean){allClean();}}});}private void allClean(){lengthOfa.setText("");lengthOfb.setText("");lengthOfc.setText("");result_1.setText("这个三角形是：");result_2.setText("面积是：       周长是：");}
}