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package cn.edu.hbcit.util;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.util.Random;import javax.imageio.ImageIO;import javax.imageio.stream.ImageOutputStream;//闂呫劍顭奸弫鎼侇敚public class RandomNumUtil {	private ByteArrayInputStream image;// 閸ユ儳鍎�	private String str;// 妤犲矁鐦夐惍锟�	private RandomNumUtil() {		init();// 閸掓繂顬婇崠鏍х潣閹拷	}	/*	 * 閸欐牕绶盧andomNumUtil鐎圭偘绶�	 */	public static RandomNumUtil Instance() {		return new RandomNumUtil();	}	/*	 * 閸欐牕绶辨宀冪槈閻礁娴橀悧锟�	 */	public ByteArrayInputStream getImage() {		return this.image;	}	/*	 * 閸欐牕绶遍崶鍓у閻ㄥ嫰鐛欑拠浣虹垳()	 */	public String getString() {		return this.str;	}	private void init() {		// 閸︺劌鍞寸�妯硅厬閸掓稑缂撻崶鎹愯杽		int width = 63, height = 20;		BufferedImage image = new BufferedImage(width, height,				BufferedImage.TYPE_INT_RGB);		// 閼惧嘲褰囬崶鎯ц埌娑撳﹣绗呴弬锟�		Graphics g = image.getGraphics();		// 閻㈢喐鍨氶梾蹇旀簚缁拷		Random random = new Random();		// 鐠佹儳鐣鹃懗灞炬珯閼癸拷		g.setColor(getRandColor(200, 250));		g.fillRect(0, 0, width, height);		// 鐠佹儳鐣剧�妞剧秼		g.setFont(new Font("Times New Roman", Font.PLAIN, 18));		// 闂呭繑婧�禍褏鏁�55閺夆�鍏遍幍鎵殠閿涘奔濞囬崶鎹愯杽娑擃厾娈戠拋銈堢槈閻椒绗夐弰鎾诡枂閸忚泛鐣犵粙瀣碍閹恒垺绁撮崚锟�		g.setColor(getRandColor(160, 200));		for (int i = 0; i < 155; i++) {			int x = random.nextInt(width);			int y = random.nextInt(height);			int xl = random.nextInt(12);			int yl = random.nextInt(12);			g.drawLine(x, y, x + xl, y + yl);		}		// 閸欐牠娈㈤張杞伴獓閻㈢喓娈戠拋銈堢槈閻拷6娴ｅ秵鏆熺�锟�		String sRand = "";		for (int i = 0; i < 4; i++) {			String rand = String.valueOf(random.nextInt(10));			sRand += rand;			// 鐏忓棜顓荤拠浣虹垳閺勫墽銇氶崚鏉挎禈鐠炩�鑵�			g.setColor(new Color(20 + random.nextInt(110), 20 + random					.nextInt(110), 20 + random.nextInt(110)));			// 鐠嬪啰鏁ら崙鑺ユ殶閸戠儤娼甸惃鍕杹閼硅尙娴夐崥宀嬬礉閸欘垵鍏橀弰顖氭礈娑撹櫣顬岀�鎰亰閹恒儴绻庨敍灞惧娴犮儱褰ч懗鐣屾纯閹恒儳鏁撻幋锟�			g.drawString(rand, 13 * i + 6, 16);		}		// 鐠у锟芥宀冪槈閻拷		this.str = sRand;		// 閸ユ崘钖勯悽鐔告櫏		g.dispose();		ByteArrayInputStream input = null;		ByteArrayOutputStream output = new ByteArrayOutputStream();		try {			ImageOutputStream imageOut = ImageIO					.createImageOutputStream(output);			ImageIO.write(image, "JPEG", imageOut);			imageOut.close();			input = new ByteArrayInputStream(output.toByteArray());		} catch (Exception e) {			System.out.println("妤犲矁鐦夐惍浣告禈閻楀洣楠囬悽鐔峰毉閻滀即鏁婄拠顖ょ窗" + e.toString());		}		this.image = input;/* 鐠у锟介崶鎯у剼 */	}	/*	 * 缂佹瑥鐣鹃懠鍐ㄦ纯閼惧嘲绶遍梾蹇旀簚妫版粏澹�	 */	private Color getRandColor(int fc, int bc) {		Random random = new Random();		if (fc > 255)			fc = 255;		if (bc > 255)			bc = 255;		int r = fc + random.nextInt(bc - fc);		int g = fc + random.nextInt(bc - fc);		int b = fc + random.nextInt(bc - fc);		return new Color(r, g, b);	}}

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