java - PropertyPlaceholderConfigurer 和 PropertySourcesPlaceholderConfigurer 的运行方式不同

Question

我使用DES算法对jdbc.properties中的用户名和密码进行加密，并使用PropertyPlaceholderConfigurer进行解密，但发现该类已被弃用。所以使用PropertySourcesPlaceholderConfigurer来代替。

spring-dao.xml中已经添加了bean，并且类中填充了包含继承自PropertySourcesPlaceholderConfigurer的解密方法的类。

我在解密方法的第一行打了断点，然后启动tomcat发送访问请求。此时，后端应该调用数据库。 但是如果解密类继承自PropertySourcesPlaceholderConfigurer，则解密方法的第一行不会被执行。如果解密类继承自PropertyPlaceholderConfigurer，则执行解密方法的第一行。我不知道为什么会这样，是否应该使用已弃用的PropertyPlaceholderConfigurer？

spring.版本:5.2.0.RELEASE

spring-dao.xml 的一部分

<!--<context:property-placeholder location="classpath:jdbc.properties" />-->
<bean class="com.imooc.o2o.util.EncryptPropertySourcesPlaceholderConfigurer">
    <property name="locations">
        <list>
            <value>classpath:jdbc.properties</value>
        </list>
    </property>
    <property name="fileEncoding" value="UTF-8" />
</bean>

EncryptPropertySourcesPlaceholderConfigurer.java(我的解密算法类)

package com.imooc.o2o.util;

import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;

public class EncryptPropertySourcesPlaceholderConfigurer extends PropertySourcesPlaceholderConfigurer {
    // Fields to be encrypted
    private String[] encryptPropNames = {"jdbc.username", "jdbc.password"};

    /**
     * Transform key attributes
     * @param propertyName
     * @param propertyValue
     * @return
     */
    @Override
    protected String convertProperty(String propertyName, String propertyValue) {
        if (isEncryptProp(propertyName)) {
            // Decrypting encrypted fields
            String decryptValue = DESUtil.getDecryptString(propertyValue);
            return decryptValue;
        } else {
            return propertyValue;
        }
    }

    /**
     * Whether the attribute is encrypted
     * @param propertyName
     * @return
     */
    private boolean isEncryptProp(String propertyName) {
        // If it is equal to the field to be encrypted, it has been encrypted
        for (String encryptPropertyName : encryptPropNames) {
            if (encryptPropertyName.equals(propertyName)) {
                return true;
            }
        }
        return false;
    }
}

DESUtil.java

package com.imooc.o2o.util;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import java.security.Key;
import java.security.SecureRandom;
import java.util.Base64;

/**
 * DES is a symmetric encryption algorithm. The so-called symmetric encryption algorithm is an algorithm that uses the same key for encryption and decryption.
 */
public class DESUtil {
    private static Key key;
    private static String KEY_STR = "myKey";
    private static String CHAR_SET_NAME = "UTF-8";
    private static String ALGORITHM = "DES";

    static {
        try {
            // Generate DES Algorithm Object
            KeyGenerator generator = KeyGenerator.getInstance(ALGORITHM);
            // Apply SHA1 security policy
            SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
            // Setting the key seed
            secureRandom.setSeed(KEY_STR.getBytes());
            // Initialize SHA1-based algorithm objects
            generator.init(secureRandom);
            // Generate a key object
            key = generator.generateKey();
            generator = null;
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    // Get encrypted information
    public static String getEncryptString(String str) {
        // Based on BASE64 encoding, receive byte [] and convert to String
        Base64.Encoder encoder = Base64.getEncoder();
        try {
            // Encoded as UTF-8
            byte[] bytes = str.getBytes(CHAR_SET_NAME);
            // Get the encrypted object
            Cipher cipher = Cipher.getInstance(ALGORITHM);
            // Initialize password information
            cipher.init(Cipher.ENCRYPT_MODE, key);
            // encryption
            byte[] doFinal = cipher.doFinal(bytes);
            // byte[] to encode a good String and return
            return encoder.encodeToString(doFinal);
        } catch (Exception e) {
            throw new RuntimeException();
        }
    }

    // Get the decrypted information
    public static String getDecryptString(String str) {
        // Based on BASE64 encoding, receive byte[] and convert to String
        Base64.Decoder decoder = Base64.getDecoder();
        try {
            // Decode string into byte []
            byte[] bytes = decoder.decode(str);
            // Get the decrypted object
            Cipher cipher = Cipher.getInstance(ALGORITHM);
            // Initialize decryption information
            cipher.init(Cipher.DECRYPT_MODE, key);
            byte[] doFinal = cipher.doFinal(bytes);
            // Returns the decrypted information
            return new String(doFinal, CHAR_SET_NAME);
        } catch (Exception e) {
            throw new RuntimeException();
        }
    }

    /**
     * Get the string to be encrypted
     * @param args
     */
    public static void main(String[] args) {
        System.out.println(getEncryptString(""));
        System.out.println(getEncryptString(""));
    }
}

Answer 1

回答我自己的问题，可能是因为我没有使用Spring Boot。

这两个类的实现逻辑是不同的。 Spring Boot 使用 PropertySourcesPlaceholderConfigurer。

这个答案不准确。我是初学者，很多地方没搞明白。偏差较大请谅解。