package StringBuilderTest;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class FrameTest extends JFrame {
private JPanel panel,button_panel;
private JTextArea notice_ta;
private JTextArea input_ta;
private JTextArea output_ta;
private JButton action_button;
private JScrollPane scroll,scroll1;
public FrameTest(){
panel=new JPanel();
panel.setLayout(new GridLayout(4,1));
notice_ta=new JTextArea(8,60);
input_ta=new JTextArea(8,60);
output_ta=new JTextArea(8,60);
scroll=new JScrollPane(input_ta);
scroll1=new JScrollPane(output_ta);
action_button=new JButton("split");
button_panel=new JPanel();
button_panel.add(action_button);
panel.add(notice_ta);
panel.add(scroll);
panel.add(button_panel);
panel.add(scroll1);
notice_ta.append("说明:\n");
notice_ta.append("在下面文本框输入需要的文本:");
add(panel);
action_button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
String userInput=input_ta.getText();
//利用split()方法分割字符串
String[] lines=userInput.split(",|,");
//因为字符串是一个整体,对字符串操作其实是创建了新的字符串,原来的字符串会被垃圾回收器回收,
//建立字符串构造器可减少,垃圾数量有利于程序运行。利用toString()方法把构造器的内容串联成一个字符串
StringBuilder sbuilder=new StringBuilder();
for(String line:lines){
sbuilder.append(line+"\n");
}
output_ta.setText(sbuilder.toString());
}
});
pack();
}
}