SpringBoot(四)---配置文件占位符

在我们配置properties文件时，可以通过文件占位符使用属性文件中的其他属性值。

举个例子：

ConfigBean.java

package com.zk.myspringboot_003;
 
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;
 
@Component
@ConfigurationProperties(prefix = "demo")
@PropertySource(value = {"classpath:application.properties"})
public class ConfigBean {
    private String name;
     
    private String age;
 
    private Map<String, String> login=new HashMap<String,String>();
     
    private List<String> urls=new ArrayList<String>();
     
     
     
    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;
    }
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public String getAge() {
        return age;
    }
 
    public void setAge(String age) {
        this.age = age;
    }
 
    @Override
    public String toString() {
        return "ConfigBean [name=" + name + ", age=" + age + ", login=" + login + ", urls=" + urls + "]";
    }
     
     
}

SpringBootApp.java

package com.zk.myspringboot_003;
 
import java.io.IOException;
import java.util.Properties;
 
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.event.ApplicationStartedEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.context.annotation.ImportResource;
import org.springframework.core.io.support.PropertiesLoaderUtils;
 
@SpringBootApplication
@ImportResource(locations={"classpath:beans.xml"})
//@ImportResource：导入spring配置文件让配置文件的内容生效
public class SpringBootApp implements ApplicationListener<ApplicationStartedEvent>{
 
    public static void main(String[]args){
        SpringApplication.run(SpringBootApp.class, args);
    }
 
    @Override
    public void onApplicationEvent(ApplicationStartedEvent event) {
        // TODO Auto-generated method stub
        Properties properties;
        try {
            properties = PropertiesLoaderUtils.loadAllProperties("classpath:application.properties");
            System.out.println(properties);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
         
    }
}

TestController.java

package com.zk.myspringboot_003;
 
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.env.Environment;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
 
@RestController
public class TestController {
     
    @Value("${demo.name}")
    private String name;
    @Value("${demo.age}")
    private String age;
     
     
    @Autowired
    private Environment environment;
//  @Autowired
//  private ConfigBeanValue configbeanValue;
     
    @Autowired
    private ConfigBean configBeanProp;
    @RequestMapping("/demo")
    public String hello()
    {
        return "hello,"+name+",you are "+age+"demo1";
    }
     
    @RequestMapping("/demo2")
    public String getprops(){
        String name=environment.getProperty("demo.name");
        String age=environment.getProperty("demo.age");
        List<String> urlslist=configBeanProp.getUrls();
        Map<String,String> loginmap=configBeanProp.getLogin();
        for(Entry<String, String> e:loginmap.entrySet())
        {
            System.out.println(e.getKey()+":"+e.getValue());
        }
        return "hello,"+name+".you are "+age+"demo2\n"+urlslist.toString()+"\n"+loginmap.get("username");
    }
     
    @RequestMapping("/demo3")
    public String getBean(){
        String name=configBeanProp.getName();
        String age=configBeanProp.getAge();
        return "hello,"+name+".you are "+age+"demo3";
    }
}

application.properties

demo.name=zk${demo.age}
demo.age=25${random.uuid}_age
#map
demo.login[username]=zhangdeshuai
demo.login[password]=zhenshuai
demo.login[callback]=http://www.flyat.cc
#list
demo.urls[0]=http://ztool.cc
demo.urls[1]=http://ztool.cc/format/js
demo.urls[2]=http://ztool.cc/str2image
demo.urls[3]=http://ztool.cc/json2Entity
demo.urls[4]=http\://ztool.cc/ua　　