Struts2学习：Action获取properties文件的值

配置文件路径：

配置内容：

方法一：

Action内被调用的函数添加下段代码：

Properties props = new Properties();
props.load(UploadFileAction.class.getClassLoader().getResourceAsStream("/struts/struts-config.properties"));
System.out.println(props.getProperty("destPath"));

执行效果：

为了便于其他Action重用，可以将此部分写成一个工具类：

package com.struts2demo.demo.util;

import com.opensymphony.xwork2.Action;

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

public class StrutsConfig {

    public Properties GetProperties(Class actionClass) throws IOException {
        Properties props = new Properties();
        props.load(actionClass.getClassLoader().getResourceAsStream("/struts/struts-config.properties"));
        return props;
    }

}

然后Action里如此调用即可：

Properties props = new StrutsConfig().GetProperties(UploadFileAction.class);
System.out.println(props.getProperty("destPath"));

方法二：@ConfigurationProperties + @PropertySource

package com.example.spdemo.controller;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.PropertySource;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@ConfigurationProperties
@PropertySource("/struts/struts-config.properties")
public class Index {

    private String destPath;

    @RequestMapping("/")
    public String getProps() {
        return destPath;
    }

    public String getDestPath() {
        return destPath;
    }

    public void setDestPath(String destPath) {
        this.destPath = destPath;
    }

}

对于非application.properties的配置，需@PropertySource指明配置文件的路径；否则默认是从application.properties中读取配置，不需要写该注解。

方法三：spring的xml配置中配置上properties，然后通过@Value注入（该方法在Spring MVC中验证过，但是不知道集成struts2后是否受影响）

spring-context.xml

<util:properties id="APP_PROP" local-override="true" location="classpath:owlforest.properties" />

owlforest.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/linfu_test_db?useUnicode=true&characterEncoding=utf-8
jdbc.username=root
jdbc.password=root

代码样例：

package com.owlforest.www.config.dao;

import com.alibaba.druid.pool.DruidDataSource;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;

@Configuration
public class DataSourceConfiguration {
    @Value("#{APP_PROP['jdbc.driver']}")
    private String driver;

    @Value("#{APP_PROP['jdbc.url']}")
    private String url;

    @Value("#{APP_PROP['jdbc.username']}")
    private String username;

    @Value("#{APP_PROP['jdbc.password']}")
    private String password;

    public DruidDataSource createDataSource(){
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driver);
        dataSource.setUrl(url);
        dataSource.setUsername(username);
        dataSource.setPassword(password);
        dataSource.setDefaultAutoCommit(true);
        return dataSource;
    }
}

 方法四：使用spring的PropertiesFactoryBean

    @Bean
    public PropertiesFactoryBean getProperties() {
        PropertiesFactoryBean propertiesFactoryBean = new PropertiesFactoryBean();
        propertiesFactoryBean.setLocations(new ClassPathResource("application.properties"));
        return propertiesFactoryBean;
    }

调用：

    @Autowired
    private PropertiesFactoryBean propertiesFactoryBean;

    public String getProperties(String key) throws IOException {
        Properties properties = propertiesFactoryBean.getObject();
        return properties.getProperty(key);
    }

 方法五：不使用自动装配，使用classLoader获取Properties

MailUtil.class.getClassLoader().getResourceAsStream("/config.properties")