Google开发的QRcode二维码生成和解码及最大容量

1.源码

package com.test;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.CharacterCodingException;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.util.Hashtable;
import javax.imageio.ImageIO;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.LuminanceSource;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.Result;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.QRCodeWriter;

public class main {
public static void main(String[] args) {
String filePath = "d:/qr_png.png";
String str = "";
/*
for (int i = 0; i < 2685; i++) {
str += 1;
}
*/

for (int i = 0; i < 635; i++) {
str += "赵";
}

encode(str, filePath);
decode(filePath);
}

// qrcode 编码
static void encode(String conent, String filePath) {
Charset charset = Charset.forName("UTF-8");
CharsetEncoder encoder = charset.newEncoder();
byte[] b = null;
try { // Convert a string to ISO-8859-1 bytes in a ByteBuffer
System.out.println("-------->" + conent.length());
ByteBuffer bbuf = encoder.encode(CharBuffer.wrap(conent));
b = bbuf.array();
} catch (CharacterCodingException e) {
System.out.println(e.getMessage());
}
String data = "";
try {
data = new String(b, "iso8859-1");
} catch (UnsupportedEncodingException e) {
System.out.println(e.getMessage());
} // get a byte matrix for the data
BitMatrix matrix = null;
int h = 900;
int w = 800;
com.google.zxing.Writer writer = new QRCodeWriter();
try {
matrix = writer.encode(data,
com.google.zxing.BarcodeFormat.QR_CODE, w, h);
} catch (com.google.zxing.WriterException e) {
System.out.println(e.getMessage());
}
File file = new File(filePath);
try {
MatrixToImageWriter.writeToFile(matrix, "PNG", file);
System.out.println("printing to " + file.getAbsolutePath());
} catch (IOException e) {
System.out.println(e.getMessage());
}
}

// qrcode 解码
static void decode(String file) {
try {
Result result = null;
BufferedImage image = null;
image = ImageIO.read(new File(file));
LuminanceSource source = new BufferedImageLuminanceSource(image);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
hints.put(DecodeHintType.CHARACTER_SET, "UTF-8");
result = new MultiFormatReader().decode(bitmap, hints);
String rtn = result.getText();
System.out.println(rtn);
System.out.println(rtn.length());
} catch (Exception ex) {
System.out.println(ex.toString());
}
}
}

2.最多2685个字母635个汉字

635个汉字

2685个字母