反射综合案例-读取properties文件

结构

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现有properties文件两个：bean.properties和data.properties

bean.properties:

id=id001
className=com.domain.User

data.properties:

uid=u001
userName=jack
password=1234

两个类：beanConfig.java和User.java

beanConfig.java:

package com.domain;

import java.util.Properties;

public class BeanConfig {
    private String id;
    private String className;
    Properties properties = new Properties();

    public BeanConfig(String id, String className, Properties properties) {
        this.id = id;
        this.className = className;
        this.properties = properties;
    }

    public BeanConfig() {
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getClassName() {
        return className;
    }

    public void setClassName(String className) {
        this.className = className;
    }

    public Properties getProperties() {
        return properties;
    }

    public void setProperties(Properties properties) {
        this.properties = properties;
    }

    @Override
    public String toString() {
        return "BeanConfig{" +
                "id='" + id + '\'' +
                ", className='" + className + '\'' +
                ", properties=" + properties +
                '}';
    }
}

User.java:

package com.domain;

public class User {
    private String uid;
    private String userName;
    private String password;

    public User(String uid, String userName, String password) {
        this.uid = uid;
        this.userName = userName;
        this.password = password;
    }

    public User() {
    }

    public String getUid() {
        return uid;
    }

    public void setUid(String uid) {
        this.uid = uid;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public String toString() {
        return "User{" +
                "uid='" + uid + '\'' +
                ", userName='" + userName + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

方法

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将两个.properties文件信息封装到 beanConfig.java中，接着用反射机制将数据封装到User的实例中

***********************************************************************************************************************************************************************************************************

具体操作

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package com.test;

import com.domain.BeanConfig;
import org.junit.Test;

import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.lang.reflect.Method;
import java.util.Properties;

public class Demo_03 {
    //获取配置文件信息
    public BeanConfig getBeanConfig() throws Exception{
        BeanConfig beanConfig = new BeanConfig();
        //读取bean.properties文件
        Properties beanProperties = new Properties();
        beanProperties.load(new InputStreamReader(new FileInputStream("bean.properties"),"UTF-8"));
        beanConfig.setId(beanProperties.getProperty("id"));
        beanConfig.setClassName(beanProperties.getProperty("className"));

        //读取data.properties文件
        Properties dataProperties = new Properties();
        dataProperties.load(new InputStreamReader(new FileInputStream("data.properties"),"UTF-8"));
        for(String name:dataProperties.stringPropertyNames()){
            String dataVlaue = dataProperties.getProperty(name);
            beanConfig.getProperties().setProperty(name,dataVlaue);
        }
        return beanConfig;
    }

    @Test
    public void demo_01() throws Exception{
        BeanConfig beanConfig = getBeanConfig();
        Class clazz = Class.forName(beanConfig.getClassName());
        Object object = clazz.newInstance();
        for(String name:beanConfig.getProperties().stringPropertyNames()){
            //***遍历方式***
            String value = beanConfig.getProperties().getProperty(name);
            String methodName = "set"+name.substring(0,1).toUpperCase()+name.substring(1);
            Method method = clazz.getMethod(methodName,String.class);
            method.invoke(object,value);
        }
        System.out.println(object);
    }
}

运行结果

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^_^