【java】ResourceBundle读取properties文件

小半 • 2023年2月5日上午10:45 • 技术随笔 • 阅读 241

一.普通java项目

1.目录结构

注意:db.properties放在src目录下

2.App代码示例

package com.test;

import java.util.ResourceBundle;

public class App {
    public static void main(String[] args) {
    	//放src目录下的db.properties
        ResourceBundle resource = ResourceBundle.getBundle("db");
        String key = resource.getString("driver");
        System.out.println(key);
    }
}

3.db.properties文件示例

driver=com.mysql.cj.jdbc.Driver

4.结果示例

5.db.properties放指定目录下

1.目录结构

//App代码示例
package com.test;

import java.util.ResourceBundle;

public class App {
    public static void main(String[] args) {
    	//包名+文件名
        ResourceBundle resource = ResourceBundle.getBundle("com.test.db");
        String key = resource.getString("driver");
        System.out.println(key);
    }
}

二.maven项目

1.maven项目properties需要放在resources文件夹目录下
2.直接放包名中是无效的

1.目录结构

2.App代码示例

package com.xiaoi;

import java.util.ResourceBundle;

public class App {
    public static void main( String[] args ) {
        ResourceBundle resource = ResourceBundle.getBundle("db");
        String key = resource.getString("driver");
        System.out.println("key"+key);
    }
}

3.db.properties示例

driver=com.mysql.cj.jdbc.Driver

4.如果放包里会出现异常

Exception in thread "main" java.util.MissingResourceException: Can't find bundle for base name db, locale zh_CN
	at java.util.ResourceBundle.throwMissingResourceException(ResourceBundle.java:1581)
	at java.util.ResourceBundle.getBundleImpl(ResourceBundle.java:1396)
	at java.util.ResourceBundle.getBundle(ResourceBundle.java:782)
	at com.xiaoi.App.main(App.java:10)