java如何实现参数绑定

配置文件读取

package cn.idea360.assistant;

import cn.idea360.assistant.properties.CommonDataSourceProperties;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.support.DefaultConversionService;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.DefaultResourceLoader;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.io.support.PropertiesLoaderUtils;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Method;
import java.util.Properties;

/**
 * @author cuishiying
 */
@Slf4j
public class ConfigLoadTest {

    @Test
    public void load_properties() throws IOException {
        ClassPathResource resource = new ClassPathResource("db.properties");
        Properties properties = PropertiesLoaderUtils.loadProperties(resource);
        properties.forEach((k, v) -> {
            log.info("{}: {}", k, v);
        });
    }

    @Test
    public void load_properties1() throws IOException {
        InputStream inputStream = ConfigLoadTest.class.getClassLoader().getResourceAsStream("db.properties");
        Properties properties = new Properties();
        properties.load(inputStream);
        properties.forEach((k, v) -> {
            log.info("{}: {}", k, v);
        });
    }

    @Test
    public void load_properties2() throws IOException {
        ResourceLoader resourceLoader = new DefaultResourceLoader();
        Resource resource = resourceLoader.getResource("classpath:db.properties");
        InputStream inputStream = resource.getInputStream();
        Properties properties = new Properties();
        properties.load(inputStream);
        properties.forEach((k, v) -> {
            log.info("{}: {}", k, v);
        });
    }

}

配置binder

package cn.idea360.assistant;

import cn.idea360.assistant.properties.CommonDataSourceProperties;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import org.junit.Before;
import org.junit.Test;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.support.GenericConversionService;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.io.InputStream;
import java.lang.reflect.Method;
import java.util.Properties;

/**
 * @author cuishiying
 */
@Slf4j
public class BaseTest {

    protected CommonDataSourceProperties sourceProperties;

    protected CommonDataSourceProperties targetProperties;

    @SneakyThrows
    private Properties loadProperties() {
        InputStream inputStream = ConfigLoadTest.class.getClassLoader().getResourceAsStream("db.properties");
        Properties properties = new Properties();
        properties.load(inputStream);
        return properties;
    }

    @SneakyThrows
    private <T> T binder(Properties properties, Class<T> beanClass, String prefix) {
        T bean = beanClass.getDeclaredConstructor().newInstance();
        BeanInfo beanInfo = Introspector.getBeanInfo(beanClass);
        PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();

        for (PropertyDescriptor propertyDescriptor : propertyDescriptors) {
            String propertyName = propertyDescriptor.getName();
            String propertyValue = properties.getProperty(prefix + "." + propertyName);
            if (propertyValue != null) {
                Method setter = propertyDescriptor.getWriteMethod();
                Class<?> propertyType = propertyDescriptor.getPropertyType();
                Object convertValue = convertValue(propertyValue, propertyType);
                setter.invoke(bean, convertValue);
            }
        }
        return bean;
    }

    private Object convertValue(String propertyValue, Class<?> propertyType) {
        ConversionService conversionService = new GenericConversionService();
        return conversionService.convert(propertyValue, propertyType);
    }

    @Before
    public void init() {
        Properties properties = loadProperties();
        this.sourceProperties = binder(properties, CommonDataSourceProperties.class, "assistant.source");
        this.targetProperties = binder(properties, CommonDataSourceProperties.class, "assistant.target");
    }

    @Test
    public void log_init() {
        log.info("base test init success");
    }

}