SQL 清空数据库的所有表数据

package com.qrcode;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
import com.swetake.util.Qrcode;

public class QRCodeGenerator {
private static QRCodeGenerator qrCodeGenerator = new QRCodeGenerator();

private QRCodeGenerator(){}

public static QRCodeGenerator getInstance(){
return qrCodeGenerator;
}

public void generatrQRCode(String content, String imgPath) {
try {

Qrcode qrcodeHandler = new Qrcode();
qrcodeHandler.setQrcodeErrorCorrect('M');
qrcodeHandler.setQrcodeEncodeMode('B');
qrcodeHandler.setQrcodeVersion(7);

byte[] contentBytes = content.getBytes();

BufferedImage bufImg = new BufferedImage(140, 140, BufferedImage.TYPE_INT_RGB);

Graphics2D gs = bufImg.createGraphics();

gs.setBackground(Color.WHITE);
gs.clearRect(0, 0, 140, 140);

// 设定图像颜色> BLACK
gs.setColor(Color.BLACK);

// 设置偏移量 不设置可能导致解析出错
int pixoff = 2;
// 输出内容> 二维码
if (contentBytes.length > 0 && contentBytes.length < 120) {
boolean[][] codeOut = qrcodeHandler.calQrcode(contentBytes);
for (int i = 0; i < codeOut.length; i++) {
for (int j = 0; j < codeOut.length; j++) {
if (codeOut[j][i]) {
gs.fillRect(j * 3 + pixoff, i * 3 + pixoff, 3, 3);
}
}
}
} else {
System.err.println("QRCode content bytes length = "+contentBytes.length + " not in [ 0,120 ]. ");
}

gs.dispose();
bufImg.flush();

File imgFile = new File(imgPath);

// 生成二维码QRCode图片
ImageIO.write(bufImg, "png", imgFile);

} catch (Exception e) {
throw new RuntimeException(e);
}

}
}

package com.qrcode;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
import jp.sourceforge.qrcode.QRCodeDecoder;
import jp.sourceforge.qrcode.data.QRCodeImage;

public class QRCodeParser {
private static QRCodeParser qrCodeParser = new QRCodeParser();

private QRCodeParser(){}

public static QRCodeParser getInstance(){
return qrCodeParser;
}

public String parseQRCode(String imgPath) {
File imageFile = new File(imgPath);

BufferedImage bufImg = null;
String decodedData = null;
try {
bufImg = ImageIO.read(imageFile);

QRCodeDecoder decoder = new QRCodeDecoder();
decodedData = new String(decoder.decode(new J2SEImage(bufImg)));

} catch (Exception e) {
throw new RuntimeException(e);
}
return decodedData;
}

private class J2SEImage implements QRCodeImage {
private BufferedImage bufImg;

public J2SEImage(BufferedImage bufImg) {
this.bufImg = bufImg;
}

public int getWidth() {
return bufImg.getWidth();
}

public int getHeight() {
return bufImg.getHeight();
}

public int getPixel(int x, int y) {
return bufImg.getRGB(x, y);
}

}
}

package com.qrcode;

public class Main {
public static void main(String[] args) {
String content="这是我的QRCode";
String imgPath="E:/mine/j2ee/QRCode/src/main/java/abc.png";
QRCodeGenerator.getInstance().generatrQRCode(content, imgPath);

String result = QRCodeParser.getInstance().parseQRCode(imgPath);
System.out.println(result);
}
}