《Java语言程序设计》试卷（A）答案.doc

1class ComplexNumber private double a,b; (1分) ComplexNumber()(1分) a=0; b=0; ComplexNumber(double a,double b) (1分) this.a=a; this.b=b; public double getA()(1分) return a; public double getB()(1分) return b; public ComplexNumber add(ComplexNumber c) (1分) return new ComplexNumber(a+c.getA(),b+c.getB(); public ComplexNumber sub(ComplexNumber c) (1分) return new ComplexNumber(a-c.getA(),b-c.getB(); public boolean equals(ComplexNumber c) (1分) return (a=c.getA & b=c.getB(); public String toString()(1分) return a + + + b + i; class ComplexNumberTest public static void main(String args) ComplexNumber cn1=new ComplexNumber(); ComplexNumber cn2=new ComplexNumber(12,34); (上述2行1分) ComplexNumber cn3=cn1.add(cn2); ComplexNumber cn4=cn1.sub(cn2); (上述2行1分) System.out.println(cn1+” equals ”+cn2+”?”+cn1.equals(cn2); (1分) 2import java.awt.*;import java.awt.event.*;/( 上述2行共1分)class CompareNum extends WindowAdapter implements ActionListener(1分) TextField tf1=new TextField(10); TextField tf2=new TextField(10); Frame f=new Frame(整数大小比较);(上述3行共1分) public static void main(String args) new CompareNum().go(); void go() Label l1=new Label(第一个整数:); Label l2=new Label(第二个整数:); (上述2行共1分) Button b=new Button(比较); f.setLayout(new FlowLayout();(上述2行共1分) f.add(l1); f.add(tf1); f.add(l2); f.add(tf2); f.add(b); (上述5行共1分) b.addActionListener(this); f.addWindowListener(this); (上述2行共1分) f.pack();/或f.setSize(100,10); f.setVisible(true); (上述2行共1分) public void actionPerformed(ActionEvent ev) (1分) int num1=0,num2=0; (1分) try num1=Integer.parseInt(tf1.getText(); catch(NumberFormatException e) javax.swing.JOptionPane.showMessageDialog(f,第一个数格式错误!); (上述6行1分) try num2=Integer.parseInt(tf2.getText(); catch(NumberFormatException e) javax.swing.JOptionPane.showMessageDialog(f,第二个数格式错误!); (上述6行1分) if (num1num2) javax.swing.JOptionPane.showMessageDialog(f,第一个数大!); else if(num1num2) javax.swing.JOptionPane.showMessageDialog(f,第二个数大!); else javax.swing.JOptionPane