2016年計(jì)算機(jī)二級(jí)《JAVA》考前非選擇題練習(xí)

字號(hào):

二、基本操作題
    本題提示輸入年份,然后判斷該年份是否為閏年。
    importjava.io.*;
    public class javal{
    public static void main(String[]args){
    InputStreamReader ir;
    BufferedReader in;
    ir=new InputStreamReader(System.in);
    in=new BufferedReader(ir);
    int year=1900;
    System.out.print("請(qǐng)輸入年份:");
    try{
    String s=in.readLine();
    ;
    } (Exception e){
    }
    if( )
    System.OUt.println(year+"是閏年");
    else
    System.out.println(year+"不是閏年");
    }
    }
    三、簡(jiǎn)單應(yīng)用題
    本題使用下拉菜單來(lái)控制字體,窗口中有一個(gè)標(biāo)簽和一個(gè)下拉菜單,當(dāng)選中下拉菜單中的任一項(xiàng)字體時(shí),標(biāo)簽上字符串的字體就隨之改變。
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    class ComboBoxFrame extends JFrame {
    public ComboBoxFrame(){
    setTitle("java2");
    setSize(300,200);
    addWindowListener(new WindowAdapter(){
    public void windowClosing(WindowEvent e){
    System.exit(0);
    }
    });
    style=new JComboBox():
    style.setEditable(true);
    style.addhem("Serif");
    style.addItem("SansSerif");
    style.addhem("Monospaced");
    style.addhem("Dialog");
    style.addhem("Dialoglnput");
    style.addActionListener(this);
    JPanel p=new JPanel();
    P.add(style);
    getContentPane().add(p,"South");
    panel=new ComboBoxTestPanel();
    getContentPane().add(panel,"Center");
    }
    public void actionPerformed(ActionEvent evt){
    JComboBox source=(JComboBox) ;
    String item=(String)source.getSelectedhem():
    panel.setStyle(item);
    }
    private ComboBoxTestPanel panel;
    private JComboBox style;
    }
    class ComboBoxTestPanel extends JPanel{
    public ComboBoxTestPanel(){
    setStyle("Serif");
    }
    public void setStyle(String s){
    setFont(new Font(S,F(xiàn)ont.PLAIN,12));
    repaint();
    }
    public void paintComponent(Graphics g){
    super.paintComponent(g);
    9.drawString("Welcome to China!",0,50);
    }
    }
    public class java2{
    public static void main(String[]args){
    JFrame frame=new ComboBoxFrame();
    frame.show();
    }
    }
    四、綜合應(yīng)用題
    本題是一個(gè)Applet,功能是監(jiān)聽(tīng)用對(duì)于文本域中文本的選擇。頁(yè)面中有一個(gè)文本域、一個(gè)“復(fù)制”按鈕和一個(gè)文本框,選中文本域中部分文字后,單擊按鈕“復(fù)制”,所選文字將顯示在文本框中。
    import java.applet.Applet;
    import java.awt.*;
    import java.awt.event.*;
    public class java3 extends Applet implements ActionL-
    istener
    {
    TextArea ta=new TextArea(5,30);
    TextField tf=new TextField(30);
    Button button=new Button("復(fù)制");
    String text="AWT提供基本的GUl組件,\n"+"
    具有可以擴(kuò)展的超類(lèi),\n"+"它們的屬性是繼承的。\
    n":
    public void init()
    {
    setLayout(new FlowLayout(FlowLayout.left));
    ta.setText(text);
    ta.setEditable(true);
    add(ta);
    add(button);
    add(tf);
    ta.addActionListener(this);
    }
    public void actionPerformed(ActionEvent e)
    {
    String S;
    s=ta.getSelectText();
    if(e.getSource()= =button)
    tf.setText(s);
    }
    }