加密连接数据库明文密码

编写DES加密工具类

package com.o2o.util;

import java.security.Key;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class DESUtil{

    private static Key key;
    private static String KEY_STR = "myKey";
    private static String CHARSETNAME = "UTF-8";
    private static String ALGORITHM = "DES";

    static {
        try {
            //生成des算法
            KeyGenerator generator = KeyGenerator.getInstance(ALGORITHM);
            //运用sha1安全策略
            SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
            //设置上密钥种子
            secureRandom.setSeed(KEY_STR.getBytes());
            //生成密钥对象
            generator.init(secureRandom);
            key = generator.generateKey();
            generator = null;
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
    /**
     * 获取解密之后的信息
     * @param str
     * @return
     */
    public static String getEncryptString(String str) {
        //基于BASE64编码，接收byte[]并转换成String
        BASE64Encoder base64encoder = new BASE64Encoder();
        try {
            //按utf8编码
            byte[] bytes = str.getBytes(CHARSETNAME);
            //获取加密对象
            Cipher cipher = Cipher.getInstance(ALGORITHM);
            //初始化加密信息
            cipher.init(Cipher.ENCRYPT_MODE, key);
            //加密
            byte[] doFinal = cipher.doFinal(bytes);
            //byte[] to encode好的String并返回
            return base64encoder.encode(doFinal);
        } catch (Exception e) {
            // TODO: handle exception
            throw new RuntimeException(e);
        }
    }

    /**
     * 获取解密之后的信息
     * @param str
     * @return
     */
    public static String getDecryptString(String str) {
        //基于BASE64编码，接受byte[]并转换成String
        BASE64Decoder base64decoder = new BASE64Decoder();
        try {
            //将字符串decode成byte[]
            byte[] bytes = base64decoder.decodeBuffer(str);
            //获取解密对象
            Cipher cipher = Cipher.getInstance(ALGORITHM);
            //初始化解密信息
            cipher.init(Cipher.DECRYPT_MODE, key);
            //解密
            byte[] doFinal = cipher.doFinal(bytes);
            //返回解密之后的信息
             return new String(doFinal, CHARSETNAME); 
            
        } catch (Exception e) {
            // TODO: handle exception
            throw new RuntimeException(e);
        }
    }
    
    public static void main(String[] args) {
        //要加密的用户和密码，运行并复制粘贴到替换jdbc.properties配置文件对应的用户密码
        System.out.println(getEncryptString("root"));
        System.out.println(getEncryptString("root"));
        
    }

}

编写程序启动时解密类

package com.o2o.util;


import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;

public class EncryptPropertyPlaceholderConfigurer extends
        PropertyPlaceholderConfigurer {
    private String[] encryptPropNames = { "jdbc.username", "jdbc.password" };
    
    @Override
    protected String convertProperty(String propertyName, String propertyValue) {
        if (isEncryptProp(propertyName)) {
            //解密
            String decryptValue = DESUtil.getDecryptString(propertyValue);
            return decryptValue;
        } else {
            return propertyValue;
        }
    }
   //判断传过来的数据是否加密过
    private boolean isEncryptProp(String propertyName) {
        for (String encryptpropertyName : encryptPropNames) {
            if (encryptpropertyName.equals(propertyName))
                return true;
        }
        return false;
    }
}

替换xml配置文件中的<context:property-placeholder location="classpath:jdbc.properties"/>为

<bean class="com.o2o.util.EncryptPropertyPlaceholderConfigurer">
        <property name="locations">
            <list>
                <value>classpath:jdbc.properties</value>
                <!-- <value>classpath:redis.properties</value> -->
            </list>
        </property>
        <property name="fileEncoding" value="UTF-8" />
    </bean>