Java中图片文件和字符串的相互转化

import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.imageio.ImageIO;
public class TypeConverter {
private static String ImageFileFormat = "jpg";
private static StringBuffer sb1 = null;
private static BufferedImage buffImage = null;
private static ByteArrayOutputStream baos = null;
private static byte[] byteImage = null;
private static String ImageFileNameFormat = "yyyy-MM-dd_HH-mm-ss";
private static String splitSymbol = ",";
private static String[] imageStringArr = null;
// picturePath为图片文件的在磁盘上的保存路径,返回值为文件转换成字符串之后的字符串,转换过程以逗号分隔（此方法理论上也可以将非图片格式的文件转换成字符串）
public static String ImageFileToString(String picturePath) {
sb1 = new StringBuffer();
try {
buffImage = ImageIO.read(new File(picturePath));
baos = new ByteArrayOutputStream();
ImageIO.write(buffImage, ImageFileFormat, baos);
} catch (IOException e) {
e.printStackTrace();
}
byteImage = baos.toByteArray();
for (int i = 0; i < byteImage.length; i++) {
if (sb1.length() == 0) {
sb1.append(byteImage[i]);
} else {
sb1.append(splitSymbol + byteImage[i]);
}
}
return sb1.toString();
}
// pictureString为需要转换成图片文件的字符串，pictureToPath是字符串转换为图片文件之后的图片文件的保存路径
public static void StringToImageFile(String pictureString,
String pictureToPath) {
if (pictureString.contains(",")) {
imageStringArr = split(pictureString, splitSymbol);
byte[] image = new byte[imageStringArr.length];
for (int i = 0; i < imageStringArr.length; i++) {
image[i] = Byte.parseByte(imageStringArr[i]);
}
String name = saveImage(image, pictureToPath);
} else {
System.out.println("(字符串----->图片文件)不能解析的格式!");
}
}
private static String[] split(String s, String token) {
if (s == null)
return null;
if (token == null || s.length() == 0)
return new String[] { s };
int size = 0;
String[] result = new String[4];
while (s.length() > 0) {
int index = s.indexOf(token);
String splitOne = s;
if (index > -1) {
splitOne = s.substring(0, index);
s = s.substring(index + token.length());
} else {
s = "";
}
if (size >= result.length) {
String[] tmp = new String[result.length * 2];
System.arraycopy(result, 0, tmp, 0, result.length);
result = tmp;
}
if (splitOne.length() > 0) {
result[size++] = splitOne;
}
}
String[] tmp = result;
result = new String[size];
System.arraycopy(tmp, 0, result, 0, size);
return result;
}
private static BufferedImage readImage(byte[] bytes) throws IOException {
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
return ImageIO.read(bais);
}
private static String saveImage(byte[] imgages, final String saveDir) {
try {
BufferedImage bis = readImage(imgages);
DateFormat sdf = new SimpleDateFormat(ImageFileNameFormat);
String fileTime = sdf.format(new Date());
final String name = fileTime + "_" + "." + ImageFileFormat;
File f = new File(saveDir + name);
boolean istrue = false;
if (f.exists()) {
istrue = ImageIO.write(bis, ImageFileFormat, f);
} else {
f.mkdirs();
istrue = ImageIO.write(bis, ImageFileFormat, f);
}
if (istrue) {
return name;
}
} catch (Exception e) {
}
return null;
}
}