下载jar包

http://mvnrepository.com/artifact/com.google.zxing/core/2.2

代码：

package com.haier.util.qr;

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;

import javax.imageio.ImageIO;

import com.google.zxing.common.BitMatrix;

public class MatrixToImageWriter {

	private static final int BLACK = 0xFF000000;
	private static final int WHITE = 0xFFFFFFFF;

	private MatrixToImageWriter() {
	}

	public static BufferedImage toBufferedImage(BitMatrix matrix) {
		int width = matrix.getWidth();
		int height = matrix.getHeight();
		BufferedImage image = new BufferedImage(width, height,
				BufferedImage.TYPE_INT_RGB);
		for (int x = 0; x < width; x++) {
			for (int y = 0; y < height; y++) {
				image.setRGB(x, y, matrix.get(x, y) ? BLACK : WHITE);
			}
		}
		return image;
	}

	public static void writeToFile(BitMatrix matrix, String format, File file)
			throws IOException {
		BufferedImage image = toBufferedImage(matrix);
		if (!ImageIO.write(image, format, file)) {
			throw new IOException("Could not write an image of format "
					+ format + " to " + file);
		}
	}

	public static void writeToStream(BitMatrix matrix, String format,
			OutputStream stream) throws IOException {
		BufferedImage image = toBufferedImage(matrix);
		if (!ImageIO.write(image, format, stream)) {
			throw new IOException("Could not write an image of format "
					+ format);
		}
	}

}

package com.haier.util.qr;

import java.io.File;
import java.io.OutputStream;
import java.util.Hashtable;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;
import com.test.MatrixToImageWriter;

public class QRUtil {

	public static void create(String text, OutputStream stream, Integer size)
			throws Exception {
		int width = 100 + (10 * size);
		int height = 100 + (10 * size);
		// 二维码的图片格式
		String format = "jpg";
		Hashtable hints = new Hashtable();
		// 内容所使用编码
		hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
		BitMatrix bitMatrix = new MultiFormatWriter().encode(text,
				BarcodeFormat.QR_CODE, width, height, hints);

		// 1.1去白边
		int[] rec = bitMatrix.getEnclosingRectangle();
		int resWidth = rec[2] + 1;
		int resHeight = rec[3] + 1;
		BitMatrix resMatrix = new BitMatrix(resWidth, resHeight);
		resMatrix.clear();
		for (int i = 0; i < resWidth; i++) {
			for (int j = 0; j < resHeight; j++) {
				if (bitMatrix.get(i + rec[0], j + rec[1])) {
					resMatrix.set(i, j);
				}
			}
		}

		MatrixToImageWriter.writeToStream(resMatrix, format, stream);
	}

	public static void main(String[] args) throws Exception {
		String text = "http://www.baidu.com/action/page/formSub.html?mac=1111111111111111111111111111111111111111111111111111111";
		int width = 300;
		int height = 300;
		// 二维码的图片格式
		String format = "jpg";
		Hashtable hints = new Hashtable();
		// 内容所使用编码
		hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
		BitMatrix bitMatrix = new MultiFormatWriter().encode(text,
				BarcodeFormat.QR_CODE, width, height, hints);
		// 生成二维码
		File outputFile = new File("d:" + File.separator + "new.jpg");
		MatrixToImageWriter.writeToFile(bitMatrix, format, outputFile);

	}

}

二维码--Google二维码使用（java版）