微信公衆號開發_SHA1(十)

package com.igoxin.weixin.custom;

import java.security.MessageDigest;
/**
 *  SHA1加密處理
 * @author fanglanfeng
 *
 */
public final class SHA1 {
	
	   private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };  
	   
	    /** 
	     * Takes the raw bytes from the digest and formats them correct. 
	     *  
	     * @param bytes 
	     *            the raw bytes from the digest. 
	     * @return the formatted bytes. 
	     */  
	    private static String getFormattedText(byte[] bytes) {  
	        int len = bytes.length;  
	        StringBuilder buf = new StringBuilder(len * 2);  
	        // 把密文轉換成十六進制的字符串形式  
	        for (int j = 0; j < len; j++) {  
	            buf.append(HEX_DIGITS[(bytes[j] >> 4) & 0x0f]);  
	            buf.append(HEX_DIGITS[bytes[j] & 0x0f]);  
	        }  
	        return buf.toString();  
	    }  
	  
	    public static String encode(String str) {  
	        if (str == null) {  
	            return null;  
	        }  
	        try {  
	            MessageDigest messageDigest = MessageDigest.getInstance("SHA1");  
	            messageDigest.update(str.getBytes());  
	            return getFormattedText(messageDigest.digest());  
	        } catch (Exception e) {  
	            throw new RuntimeException(e);  
	        }  
	    }  

}