java get properties_java 普通方法获取 properties值

package com.zcxt.analysis;

import org.junit.Test;

import java.io.BufferedInputStream;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.util.Enumeration;

import java.util.Properties;

import java.util.PropertyResourceBundle;

import java.util.ResourceBundle;

/**

* @auth mayanze

* @date 2019/1/9

*/

public class PropertiesTest {

// 1。使用java.util.Properties 类的load()方法

// 示例：

public static String getProperties_1(String url) throws IOException {

InputStream in = new BufferedInputStream(new FileInputStream(url));

Properties p = new Properties();

p.load(in);

return p.getProperty("jdbc.type");

}

// 2。使用java.util.ResourceBundle类的getBundle()方法

// 示例：

public static void getProperties_2(String url) {

ResourceBundle rb = ResourceBundle.getBundle(url);

Enumeration keys = rb.getKeys();

while (keys.hasMoreElements()){

System.out.println(rb.getString(keys.nextElement()));

}

}

// 3。使用java.util.PropertyResourceBundle类的构造函数

// 示例：

public static void getProperties_3(String url) throws IOException {

InputStream in = new BufferedInputStream(new FileInputStream(url));

ResourceBundle rb = new PropertyResourceBundle(in);

Enumeration keys = rb.getKeys();

while (keys.hasMoreElements()){

System.out.println(rb.getString(keys.nextElement()));

}

}

// 4。使用class变量的getResourceAsStream()方法

// 示例：

public static String getProperties_4(String url) throws IOException {

InputStream in = Test.class.getResourceAsStream(url);

Properties p = new Properties();

p.load(in);

return p.getProperty("jdbc.url");

}

// 5。使用class.getClassLoader()所得到的java.lang.ClassLoader的getResourceAsStream()方法

// 示例：

public static String getProperties_5(String url) throws IOException {

InputStream in = Test.class.getClassLoader().getResourceAsStream(url);

Properties p = new Properties();

p.load(in);

return p.getProperty("jdbc.url");

}

// 6。使用java.lang.ClassLoader类的getSystemResourceAsStream()静态方法

// 示例：

public static String getProperties_6(String url) throws IOException {

InputStream in = ClassLoader.getSystemResourceAsStream(url);

Properties p = new Properties();

p.load(in);

return p.getProperty("jdbc.url");

}

//

// 补充

// Servlet中可以使用javax.servlet.ServletContext的getResourceAsStream()方法

// 示例：

// public static Properties getProperties_8(String url) {

// InputStream in = context.getResourceAsStream(url);

// Properties p = new Properties ();

// p.load(in);

// }

public static void main(String[] args) throws IOException {

// File file = new File("settings.properties");

// String sentence = FileUtils.readFileToString(file,"utf8");

//需要将文件放置到项目根目录下面

// System.out.println(getProperties_1("settings.properties"));

// System.out.println("----------");

//需要将文件放置到class文件同级目录下面

// getProperties_2("settings");

// System.out.println("----------");

// getProperties_3("settings.properties");

// System.out.println("----------");

// System.out.println(getProperties_4("settings.properties"));

// System.out.println("----------");

System.out.println(getProperties_5("settings.properties"));

System.out.println("----------");

System.out.println(getProperties_6("settings.properties"));

}

}