首先需要一个加密的类，我们这里使用的是RSAUtil类：

package com.ebs.common.util;

import org.apache.commons.codec.binary.Base64;
import org.springframework.stereotype.Component;

import javax.crypto.Cipher;
import java.io.ByteArrayOutputStream;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

@Component
public class RSAUtil {
    /**
     * RSA最大加密明文大小
     */
    private static final int MAX_ENCRYPT_BLOCK = 117;

    /**
     * RSA最大解密密文大小
     */
    private static final int MAX_DECRYPT_BLOCK = 128;

    /**
     * 默认私钥
     */
    private static final String PRIVATE_KEY = "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";
    /**
     * 默认公钥
     */
    private static final String PUBLIC_KEY = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCNu5SO299bS8NvGXM+dypDLP0BjzcuEJtwvTwjw3qkIFL/NjLT7l2a04QAZbdu88DtC34+gfhed5nDAPIzXyURjbZXoviBisJ0TToMZA2C3Y41reu6dqD3Xy1RzLZMYGtyTAqTj1Lc9ar2O5b/7pd7UXA7BdJznkZ9NA7wIDAQAB";

    /**
     * 获取密钥对
     *
     * @return 密钥对
     */
    public static KeyPair getKeyPair() throws Exception {
        KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
        generator.initialize(1024);
        return generator.generateKeyPair();
    }
    /**
     * 获取私钥
     *
     * @param
     * @return
     */
    public static PrivateKey getPrivateKey() throws Exception {
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        byte[] decodedKey = Base64.decodeBase64(PRIVATE_KEY);
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(decodedKey);
        return keyFactory.generatePrivate(keySpec);
    }

    /**
     * 获取公钥
     *
     * @param publicKey 公钥字符串
     * @return
     */
    public static PublicKey getPublicKey(String publicKey) throws Exception {
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        byte[] decodedKey = Base64.decodeBase64(publicKey.getBytes());
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(decodedKey);
        return keyFactory.generatePublic(keySpec);
    }

    /**
     * RSA加密
     *
     * @param data      待加密数据
     * @param publicKey 公钥
     * @return
     */
    public static String encrypt(String data, PublicKey publicKey) throws Exception {
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        int inputLen = data.getBytes().length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offset = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段加密
        while (inputLen - offset > 0) {
            if (inputLen - offset > MAX_ENCRYPT_BLOCK) {
                cache = cipher.doFinal(data.getBytes(), offset, MAX_ENCRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(data.getBytes(), offset, inputLen - offset);
            }
            out.write(cache, 0, cache.length);
            i++;
            offset = i * MAX_ENCRYPT_BLOCK;
        }
        byte[] encryptedData = out.toByteArray();
        out.close();
        // 获取加密内容使用base64进行编码,并以UTF-8为标准转化成字符串
        // 加密后的字符串
        return new String(Base64.encodeBase64String(encryptedData));
    }

    /**
     * RSA解密
     *
     * @param data       待解密数据
     * @param privateKey 私钥
     * @return
     */
    public static String decrypt(String data, PrivateKey privateKey) throws Exception {
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        byte[] dataBytes = Base64.decodeBase64(data);
        int inputLen = dataBytes.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offset = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段解密
        while (inputLen - offset > 0) {
            if (inputLen - offset > MAX_DECRYPT_BLOCK) {
                cache = cipher.doFinal(dataBytes, offset, MAX_DECRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(dataBytes, offset, inputLen - offset);
            }
            out.write(cache, 0, cache.length);
            i++;
            offset = i * MAX_DECRYPT_BLOCK;
        }
        byte[] decryptedData = out.toByteArray();
        out.close();
        // 解密后的内容
        return new String(decryptedData, "UTF-8");
    }

    public static void main(String[] args) {
        // 生成密钥对
        KeyPair keyPair = null;
        try {
            keyPair = getKeyPair();

            //生成私钥方法
            //String privateKey = new String(Base64.encodeBase64(keyPair.getPrivate().getEncoded()));

            String privateKey = PRIVATE_KEY;

            //生成公钥方法
            //String publicKey = new String(Base64.encodeBase64(keyPair.getPublic().getEncoded()));

            String publicKey = PUBLIC_KEY;

            System.out.println("私钥"+privateKey);
            System.out.println("公钥"+publicKey);

            // RSA加密
            String data = "{\"name\":\"admin\",\"pwd\":\"123456\",\"level\":\"1\"}";
            String encryptData = encrypt(data, getPublicKey(publicKey));
            System.out.println("加密后内容:" + encryptData);
       
            // RSA解密
            String decryptData = decrypt(encryptData, getPrivateKey());
            System.out.println("解密后内容:" + decryptData);
            
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}

然后，可以将我们的数据库配置文件信息中的username和password分别放入上面的mian方法中，然后将生成的加密后的数据再填写到对应的uaername和password中，比如：

其次更重要的来了然后再配置连接的xml文件中

找到上面的class路径，然后创建一个类，继承class=“”中的类重写其加载username和password，然后在方法中进行解密赋值，就可以正常连接了。

如果没有xml这个配置类，可以使用继承PropertyPlaceholderConfiurer，然后在里面加载数据库配置文件信息，进行解密修改spring-jdbc文件数据库配置加密 - java程序猿的点滴记录 - ITeye博客