二进制与字符串转换（图片转换）

 将一个图片转换成二进制编码，再将一个二进制字符串转换成为图片实例：

 

 

public class Test{
	public static void main(String[] args) {
		try{  
	        
	        // 将图片转换成字符串  
	        File f = new File("c:\\biao.png");  
	        FileInputStream fis = new FileInputStream( f );  
	        byte[] bytes = new byte[fis.available()];  
	        fis.read(bytes);  
	        fis.close();  
	          
	        // 生成字符串  
	        String imgStr = byte2hex( bytes );  
	        System.out.println( imgStr);  
	          
	        // 将字符串转换成二进制，用于显示图片  
	        // 将上面生成的图片格式字符串 imgStr，还原成图片显示
	        OutputStream o = new FileOutputStream("c:\\878789.png");  
	        byte[] imgByte = hex2byte( imgStr );  
	        InputStream in = new ByteArrayInputStream( imgByte );  
	        byte[] b = new byte[1024];  
	        int nRead = 0;  
	        while( ( nRead = in.read(b) ) != -1 ){  
	            o.write( b, 0, nRead );  
	        }  
	        o.flush();  
	        o.close();  
	        in.close();  
	          
	          
	    }catch(Exception e){  
	        e.printStackTrace();  
	    }finally{  
	    }  
	}
	/**
	 * 二进制转字符串
	 * @param b byte数组
	 * @return 二进制字符串
	 */
	public static String byte2hex(byte[] b){
		StringBuffer sb = new StringBuffer();
		String stmp = "";
		for (int n = 0; n < b.length; n++) {
			stmp = Integer.toHexString(b[n] & 0XFF);
			if (stmp.length() == 1) {
				sb.append("0" + stmp);
			} else {
				sb.append(stmp);
			}
		}
		return sb.toString();
	}
	/**
	 * 字符串转二进制
	 * @param str 字符串
	 * @return byte数组
	 */
	public static byte[] hex2byte(String str) {
		if (str == null)
			return null;
		str = str.trim();
		int len = str.length();
		if (len == 0 || len % 2 == 1)
			return null;
		byte[] b = new byte[len / 2];
		try {
			for (int i = 0; i < str.length(); i += 2) {
				b[i / 2] = (byte) Integer.decode("0X" + str.substring(i, i + 2)).intValue();
			}
			return b;
		} catch (Exception e) {
			return null;
		}
	}
}