Java中Properties类的操作-优快云博客

本文介绍了一种在Java中通过Properties类来读取配置文件的方法，并提供了一个具体的实现示例。该方法利用ClassLoader加载资源文件，通过Properties类实例进行属性读取。

Java中Properties类的操作

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com.gordon.constant

Constant.java:

package com.gordon.constant;

public interface Constant {
	
	/**
	 * 根据名称读取常量
	 * @param name
	 * @return
	 */
	public String get_constant(String name);
}

SystemConstant4PropImpl.java

package com.gordon.constant;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

public class SystemConstant4PropImpl implements Constant {

	public Properties prop = null;

	public SystemConstant4PropImpl() {
		InputStream in = ClassLoader.getSystemResourceAsStream("constant.properties");
		prop = new Properties();
		try {
			prop.load(in);
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	public SystemConstant4PropImpl(String prop_path) {
		InputStream in = ClassLoader.getSystemResourceAsStream(prop_path);
		prop = new Properties();
		try {
			prop.load(in);
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	/**
	 * 获取properties文件中的属性
	 */
	@Override
	public String get_constant(String name) {
		return prop.getProperty(name);
	}
}

SystemConstant4XMLImpl.java

package com.gordon.constant;

public class SystemConstant4XMLImpl {
	
}

com.grodon.test

TestConstantClass.java:

package com.gordon.test;

import org.junit.Test;

import com.gordon.constant.SystemConstant4PropImpl;

public class TestConstantClass {
	@Test
	public void run() {
		try {
			SystemConstant4PropImpl scp = new SystemConstant4PropImpl();
			String db_username = scp.get_constant("db.username");
			System.out.println(db_username);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}

constant.properties: