一般spring容器启动时，通过PropertyPlaceholderConfigurer类读取jdbc.properties文件里的数据库配置信息。
通过这个原理，我们把加密后的数据库配置信息放到jdbc.properties文件里，然后自定义一个继承PropertyPlaceholderConfigurer的类，实现解密，把解密后的信息又放回去。最后在配置DataSource时，还是用占位符${}取配置信息。本次采用的加密方式是通过MD5根据自定义键来进行加密
jdbc.properties文件：
#加密前
#jdbc.driver=数据库驱动
#jdbc.url=数据库连接地址
#jdbc.username=用户名
#jdbc.password=密码
#加密后
jdbc.driver.encryption=A551966A9AF762B92501746C2CB01B106C34B140337ADE6E602DF5FB0DA173DB
jdbc.url.encryption=4042C4E947DE0ABDE395A65B56BAC61828773933A8D94B913BED7648490C3A15683550FB33253ECD18A5C62C237FC824
jdbc.username.encryption=4DD8268D320D25322A3AAE2A37DABABA
jdbc.password.encryption=BAE996B948645DA06922BE240FF3FBBB上面加密后的东西，要先通过工具类将加密前的数据进行加密，然后再放入jdbc.properties文件中，同时注释掉加密前的内容
工具类AESHelper：
package com.lyh.domain;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.MessageDigest;
import java.security.spec.AlgorithmParameterSpec;
import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
/**
* @author 作者:LYH
* @createDate 创建时间：2018年8月14日 上午8:37:31
*/
public class AESHelper {
Cipher ecipher;
Cipher dcipher;
/**
* Input a string that will be md5 hashed to create the key.
*
* @return void, cipher initialized
*/
public AESHelper() {
try {
SecretKeySpec skey = new SecretKeySpec("0123456789ABCDEF".getBytes(), "AES");
this.setupCrypto(skey);
}
catch (Exception e) {
e.printStackTrace();
}
}
public AESHelper(String key) {
SecretKeySpec skey = new SecretKeySpec(getMD5(key), "AES");
this.setupCrypto(skey);
}
private void setupCrypto(SecretKey key) {
// Create an 8-byte initialization vector
byte[] iv = new byte[]
{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
AlgorithmParameterSpec paramSpec = new IvParameterSpec(iv);
try {
ecipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
dcipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
// CBC requires an initialization vector
ecipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);
dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec);
}
catch (Exception e) {
e.printStackTrace();
}
}
// Buffer used to transport the bytes from one stream to another
// byte[] buf = new byte[1024];
public void encrypt(InputStream in, OutputStream out) {
byte[] buf = new byte[1024];
try {
// Bytes written to out will be encrypted
out = new CipherOutputStream(out, ecipher);
// Read in the cleartext bytes and write to out to encrypt
int numRead = 0;
while ((numRead = in.read(buf)) >= 0) {
out.write(buf, 0, numRead);
}
out.close();
}
catch (java.io.IOException e) {
e.printStackTrace();
}
}
/**
* Input is a string to encrypt.
*
* @return a Hex string of the byte array
*/
public String encrypt(String plaintext) {
try {
byte[] ciphertext = ecipher.doFinal(plaintext.getBytes("UTF-8"));
return byteToHex(ciphertext);
}
catch (Exception e) {
e.printStackTrace();
return null;
}
}
public void decrypt(InputStream in, OutputStream out) {
try {
byte[] buf = new byte[1024];
// Bytes read from in will be decrypted
in = new CipherInputStream(in, dcipher);
// Read in the decrypted bytes and write the cleartext to out
int numRead = 0;
while ((numRead = in.read(buf)) >= 0) {
out.write(buf, 0, numRead);
}
out.close();
}
catch (java.io.IOException e) {
e.printStackTrace();
}
}
/**
* Input encrypted String represented in HEX
*
* @return a string decrypted in plain text
*/
public String decrypt(String hexCipherText) {
try {
String plaintext = new String(dcipher.doFinal(hexToByte(hexCipherText)), "UTF-8");
return plaintext;
}
catch (Exception e) {
e.printStackTrace();
return null;
}
}
public String decrypt(byte[] ciphertext) {
try {
String plaintext = new String(dcipher.doFinal(ciphertext), "UTF-8");
return plaintext;
}
catch (Exception e) {
e.printStackTrace();
return null;
}
}
private static byte[] getMD5(String input) {
try {
byte[] bytesOfMessage = input.getBytes("UTF-8");
MessageDigest md = MessageDigest.getInstance("MD5");
return md.digest(bytesOfMessage);
}
catch (Exception e) {
return null;
}
}
static final String HEXES = "0123456789ABCDEF";
public static String byteToHex(byte[] raw) {
if (raw == null) {
return null;
}
final StringBuilder hex = new StringBuilder(2 * raw.length);
for (final byte b : raw) {
hex.append(HEXES.charAt((b & 0xF0) >> 4)).append(HEXES.charAt((b & 0x0F)));
}
return hex.toString();
}
public static byte[] hexToByte(String hexString) {
int len = hexString.length();
byte[] ba = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
ba[i / 2] =
(byte)((Character.digit(hexString.charAt(i), 16) << 4) + Character.digit(hexString.charAt(i + 1), 16));
}
return ba;
}
//测试加密
public static void main(String[] args){
AESHelper aesHelper = new AESHelper();
System.out.println(aesHelper.encrypt("com.mysql.jdbc.Driver"));
}
}
进行解密的类实现了PropertyPlaceholderConfigurer
GvtvPropertyPlaceholderConfigurer.java
package com.lyh.domain;
import java.util.Enumeration;
import java.util.Properties;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;
/**
* @author 作者:LYH
* @createDate 创建时间：2018年8月14日 上午8:35:29
*/
public class GvtvPropertyPlaceholderConfigurer extends PropertyPlaceholderConfigurer {
@Override
protected void processProperties(ConfigurableListableBeanFactory beanFactoryToProcess, Properties props) throws BeansException {
AESHelper aesHelper = new AESHelper();
Enumeration<?> keys = props.propertyNames();
while (keys.hasMoreElements()) {
String key = (String)keys.nextElement();
String value = props.getProperty(key);
if (key.endsWith(".encryption") && null != value) {
props.remove(key);
key = key.substring(0, key.length() - 11);
value = aesHelper.decrypt(value.trim());
props.setProperty(key, value);
}
System.setProperty(key, value);
}
super.processProperties(beanFactoryToProcess, props);
}
}下面是spring的配置文件，用来读取xml中的内容：
<bean id="propertyConfigurer"
class="com.lyh.domain.GvtvPropertyPlaceholderConfigurer">
<property name="locations">
<list>
<value>classpath*:jdbc.properties</value>
</list>
</property>
</bean>
<!-- 使用dbcp配置 数据库链接池 -->
<bean id="dataSource" class="org.apache.commons.dbcp2.BasicDataSource"
destroy-method="close" lazy-init="true" depends-on="propertyConfigurer">
<property name="driverClassName" value="${jdbc.driver}" />
<property name="url" value="${jdbc.url}" />
<property name="username" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
</bean>
<!-- 取得sqlsessionFactory -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />com.lyh.domain.GvtvPropertyPlaceholderConfigurer这是自定义的类
到这里后加密解密就完成了，想要看到更加的直观的可以下载代码https://download.csdn.net/download/qq_36827957/10602489