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(); }
}