Spring Boot——读取.properties配置文件解决方案

程序员文章站 2022-05-02 11:41:19

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解决方案

Spring Boot 读取properties配置文件时，默认读取的是application.properties。

方法一：@ConfigurationProperties注解方式

@Component 表示将该类标识为Bean

@ConfigurationProperties(prefix = "demo")用于绑定属性，其中prefix表示所绑定的属性的前缀。

@PropertySource(value = "config.properties")表示配置文件路径。

import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.springframework.boot.context.properties.ConfigurationProperties;
//import org.springframework.context.annotation.PropertySource;
import org.springframework.stereotype.Component;

/**
 * @date 2017年6月1日 下午4:34:18 
 * @version V1.0
 * @since JDK ： 1.7
 */
@Component
@ConfigurationProperties(prefix = "com.zyd")
// PropertySource默认取application.properties
// @PropertySource(value = "config.properties")
public class PropertiesConfig {

    public String type3;
    public Map<String, String> login = new HashMap<String, String>();
    public List<String> urls = new ArrayList<>();

    public String getType3() {
        return type3;
    }

    public String getTitle3() {
        try {
            return new String(title3.getBytes("ISO-8859-1"), "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return title3;
    }


    public Map<String, String> getLogin() {
        return login;
    }

    public void setLogin(Map<String, String> login) {
        this.login = login;
    }

    public List<String> getUrls() {
        return urls;
    }

    public void setUrls(List<String> urls) {
        this.urls = urls;
    }

}

方法二：@Value注解方式

import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * @date 2017年6月1日 下午3:49:30 
 * @version V1.0
 * @since JDK ： 1.7
 */
@SpringBootApplication
@RestController
public class Applaction {

    @Value("${com.zyd.type}")
    private String type;

    /**
     * 
     * 第二种方式：使用`@Value("${propertyName}")`注解
     * 
     */
    @RequestMapping("/value")
    public Map<String, Object> value() throws UnsupportedEncodingException {
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("type", type);
        return map;
    }

    public static void main(String[] args) throws Exception {
        SpringApplication application = new SpringApplication(Applaction.class);
        application.run(args);
    }
}

注：如果@Value${}所包含的键名在application.properties配置文件中不存在的话，会抛出异常：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'configBeanValue': Injection of autowired dependencies failed; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'demo.name' in value "${demo.name}"

方法三：Environment

import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.core.env.Environment;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * @date 2017年6月1日 下午3:49:30
 * @version V1.0
 * @since JDK ： 1.7
 */
@SpringBootApplication
@RestController
public class Applaction {

    @Autowired
    private Environment env;

    /**
     * 
     * 第三种方式：使用`Environment`
     * 
     */
    @RequestMapping("/env")
    public Map<String, Object> env() throws UnsupportedEncodingException {
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("type", env.getProperty("com.zyd.type2"));
        return map;
    }

    public static void main(String[] args) throws Exception {
        SpringApplication application = new SpringApplication(Applaction.class);
        application.run(args);
    }
}

方法四：PropertiesLoaderUtils

https://blog.csdn.net/thc1987/article/details/78789426