我正在尝试从“文件”中读取属性,但无法达到相同的目的。
web.xml
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:ApplicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
ApplicationContext.xml
<context:annotation-config />
<context:component-scan base-package="com.jodo.image.*"></context:component-scan>
<context:property-placeholder location="file:/usr/local/jodo/opt/cms-image/db.properties"/>
<context:property-placeholder location="file:/usr/local/jodo/opt/cms-image/service.properties"/>
<util:properties id="systemPropertiesHolder" location="file:/usr/local/jodo/opt/cms-image/service.properties">
</util:properties>
第一次尝试
类ThreadFileImageUpload
public class ThreadFileImageUpload extends Thread {
private String rawImagePath;
@Value("#{systemPropertiesHolder.rawImagePath}")
public void setRawImagePath(String property){
rawImagePath = property;
}...
结果:rawImagePath为空
第二次尝试
类ThreadFileImageUpload
@Configuration
@ImportResource("classpath:properties-config.xml")
public class ThreadFileImageUpload extends Thread {
private @Value("${rawImagePath}") String rawImagePath;
properties-config.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util-3.0.xsd">
<context:property-placeholder location="file:/usr/local/jodo/opt/cms-image/service.properties"/>
</beans>
结果:rawImagePath为空
第三次尝试
类ThreadFileImageUpload
@Configuration
@PropertySource("file:/usr/local/jodo/opt/cms-image/service.properties")
public class ThreadFileImageUpload extends Thread {
@Autowired
Environment environment;
private String rawImagePath;
public void run() {
if(environment == null){
logger.info("environment is NULL");
}
rawImagePath = this.environment.getProperty("rawImagePath");
...
给出java.lang.NullPointerException(环境本身为null)
第四次尝试
类ThreadFileImageUpload
public class ThreadFileImageUpload extends Thread {
@Value("${rawImagePath}")
private String rawImagePath;
结果:rawImagePath为空
第五次尝试
ApplicationContext.xml(现在将所有文件放在一个属性占位符中)
<context:property-placeholder location="file:/usr/local/jodo/opt/cms-image/db.properties, file:/usr/local/jodo/opt/cms-image/service.properties"/>
类ThreadFileImageUpload
public class ThreadFileImageUpload extends Thread {
@Value("${rawImagePath}")
private String rawImagePath;
结果:rawImagePath为空
第六次尝试
ThreadFileImageUpload类
package com.jodo.image.util;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
@Component
public class ThreadFileImageUpload extends Thread {
@Value("#{systemPropertiesHolder.rawImagePath}")
private String rawImagePath;
AppliactionContext.xml
<context:annotation-config />
<context:component-scan base-package="com.jodo.image.*"></context:component-scan>
<util:properties id="systemPropertiesHolder" location="file:/usr/local/jodo/opt/cms-image/service.properties">
</util:properties>
仍为空
我确定该属性文件具有必填字段
[root@localhost /]# cat /usr/local/jodo/opt/cms-image/service.properties
rawImagePath=/var/jodo-images/raw/
我仍然被困在同一个地方。
最佳答案
为了使@Value工作,ThreadFileImageUpload实例必须是Spring托管的组件。请注意,使用“ new”创建的实例不受Spring的管理。参考手册here和here可以帮助您了解Spring Bean和组件扫描。
关于java - 无法使用context:property-placeholder获得属性( Spring ),我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/23168891/