springboot初始化的时候对配置文件进行处理

import org.springframework.context.ApplicationContextInitializer;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.core.env.*;

import java.util.Iterator;
import java.util.Properties;

public class PropertiesInitializer implements ApplicationContextInitializer {
    public PropertiesInitializer() {
    }

    @Override
    public void initialize(ConfigurableApplicationContext applicationContext) {
        ConfigurableEnvironment environment = applicationContext.getEnvironment();
        MutablePropertySources propertySources = environment.getPropertySources();
        Iterator it = propertySources.iterator();
        PropertySource source;
        while (it.hasNext()) {
            source = (PropertySource) it.next();
            if (!(source instanceof EnumerablePropertySource)) {
                continue;
            }
            EnumerablePropertySource enumerablePropertySource = (EnumerablePropertySource) source;
            String[] propertyNames = enumerablePropertySource.getPropertyNames();
            int length = propertyNames.length;
//获取到配置文件中的key 对key进行处理 也可以处理value，jsypt就是对ENC()包裹内容进行解密            
for (int i = 0; i < length; i++) {
                String name = propertyNames[i];
                String value = String.valueOf(source.getProperty(name));
                if (name.equals("jasypt.encryptor.replace")) {
                    Properties properties = new Properties();
                    properties.setProperty("jasypt.encryptor.password", value);
                    PropertySource propertySource = new PropertiesPropertySource("encryptor" + source.getName(), properties);
                    propertySources.addBefore(source.getName(), propertySource);
                    break;
                }

            }
        }
    }
}