Jlabel实现内容自动换行简单实例

package com.zht;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.FontMetrics;
import java.util.concurrent.TimeUnit;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class JLabelDemo extends JFrame {
	public static void main(String[] args)
	   throws InterruptedException {
		System.out.println("hello");
		JLabelDemo jLabelDemo = new JLabelDemo();
	}
	public JLabelDemo() throws InterruptedException {
		String text = "This space contains technical articles,"
		    + " blogs and discussion forums with questions and answers."
		    + "作为一个Java程序员，从论坛上感受到使用Java开发程序的人越来多，"
		    + "心中不免欣慰。hello";
		JLabel label = new JLabel();
		label.setSize(200, 0);
		//注意JLabel一定要设置宽度
		//  System.out.println(label.getWidth());
		JlabelSetText(label, text);
		setLayout(new FlowLayout());
		add(label);
		pack();
		//  setSize(300, 200);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setLocationRelativeTo(null);
		setVisible(true);
	}
	void JlabelSetText(JLabel jLabel, String longString) 
	   throws InterruptedException {
		StringBuilder builder = new StringBuilder("");
		char[] chars = longString.toCharArray();
		FontMetrics fontMetrics = jLabel.getFontMetrics(jLabel.getFont());
		int start = 0;
		int len = 0;
		while (start + len < longString.length()) {
			while (true) {
				len++;
				if (start + len > longString.length())break;
				if (fontMetrics.charsWidth(chars, start, len) 
				      > jLabel.getWidth()) {
					break;
				}
			}
			builder.append(chars, start, len-1).append("
");
			start = start + len - 1;
			len = 0;
		}
		builder.append(chars, start, longString.length()-start);
		builder.append("");
		jLabel.setText(builder.toString());
	}
}