Java实现读写属性文件工具类

╰+哭是因爲堅強的太久メ 2021-07-24 20:40 484阅读 0赞

# 一 点睛 #

我们常常需要对属性文件进行读写操作，在此提供一个工具类。

# 二 代码 #

package com.imooc.demo.common.util;
    
    import java.io.*;
    import java.util.Properties;
    
    /**
    * Copyright (C), 2020-2020, 软件公司
    * FileName: PropertiesUtils.java
    * Author:   cakin
    * Date:     2020/8/18
    * Description: 属性文件工具类
    */
    public class PropertiesUtils {
        // 默认的属性配置文件
        private String properiesName = "sysConfig.properties";
    
        public PropertiesUtils() {
        }
    
        public PropertiesUtils(String fileName) {
            this.properiesName = fileName;
        }
    
        /**
         * 功能描述：读取文件的键
         *
         * @param key 属性文件的键
         * @return String 键对应的值
         * @author cakin
         * @date 2020/8/18
         */
        public String readProperty(String key) {
            String value = "";
            InputStream is = null;
            try {
                is = PropertiesUtils.class.getClassLoader().getResourceAsStream(
                        properiesName);
                Properties p = new Properties();
                p.load(is);
                value = p.getProperty(key);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return value;
        }
    
        /**
         * 功能描述：获取Properties
         *
         * @author cakin
         * @date 2020/8/18
         */
        public Properties getProperties() {
            Properties p = new Properties();
            InputStream is = null;
            try {
                is = PropertiesUtils.class.getClassLoader().getResourceAsStream(properiesName);
                p.load(is);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return p;
        }
    
        /**
         * 功能描述：将键值对写入属性文件
         *
         * @param key   属性文件的键
         * @param value 属性文件的值
         * @author cakin
         * @date 2020/8/18
         */
        public void writeProperty(String key, String value) {
            InputStream is = null;
            OutputStream os = null;
            Properties p = new Properties();
            try {
                is = PropertiesUtils.class.getClassLoader().getResourceAsStream(properiesName);
                p.load(is);
                // 文件路径为类路径：E:/IDEA/target/classes/sysConfig.properties
                String fileName = Thread.currentThread().getContextClassLoader().getResource(properiesName).getPath();
                os = new FileOutputStream(fileName);
                p.setProperty(key, value);
                p.store(os, key);
                os.flush();
                os.close();
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if (null != is)
                        is.close();
                    if (null != os)
                        os.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    
        public static void main(String[] args) {
            // 测试 readProperty 功能
            test1();
            // 测试 getProperties 功能
            test2();
            // 将键值对写入文件
            test3();
        }
    
        /**
         * 功能描述：测试 readProperty 功能
         *
         * @author cakin
         * @date 2020/8/18
         */
        public static void test1() {
            String isSendStr = new PropertiesUtils().readProperty("is_send_message");
            if (isSendStr != null && !isSendStr.isEmpty()) {
                System.out.println(isSendStr);
            }
        }
    
        /**
         * 功能描述：测试getProperties
         *
         * @author cakin
         * @date 2020/8/18
         */
        public static void test2() {
            PropertiesUtils propertiesUtils = new PropertiesUtils();
            Properties properties = propertiesUtils.getProperties();
            String is_send_message = properties.getProperty("is_send_message");
            System.out.println(is_send_message);
        }
    
        /**
         * 功能描述：将键值对写入属性文件
         *
         * @author cakin
         * @date 2020/8/18
         */
        public static void test3() {
            PropertiesUtils propertiesUtils = new PropertiesUtils();
            propertiesUtils.writeProperty("cakin24","cakin24");
        }
    }

# 三 测试结果 #

true

# 四 测试后属性文件内容如下 #

#cakin24
    #Tue Aug 18 19:39:30 CST 2020
    is_send_message=true
    cakin24=cakin24