如何通過春季表達式語言評估作爲一個參數？

Question

這不是工作：

<?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:encryption="http://www.jasypt.org/schema/encryption" 
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
         http://www.springframework.org/schema/beans/spring-beans-3.1.xsd 
         http://www.jasypt.org/schema/encryption 
         http://www.jasypt.org/schema/encryption/jasypt-spring31-encryption-1.xsd"> 

    <import resource="properties/secure/jasypt-context.xml" /> 
    <bean name="propEnvironment" class="java.lang.String"> 
     <constructor-arg value="#{ systemProperties['property.environment'] ?: systemProperties['cfg.environment'] }" /> 
    </bean> 
    <encryption:encryptable-property-placeholder 
     encryptor="configurationEncryptor" 
     location="classpath:properties/#{propEnvironment}/*.properties,classpath:properties/common.properties" /> 

</beans> 

只有common.properties得到由可加密屬性佔位符配置。這就像其他條目剛剛消失（沒有錯誤或任何東西，它只是不加載任何其他）。我想站在生產配置文件的實例上，但我想使用我的開發屬性。如果我打印出來，拼寫表達式正在評估。這可能嗎？

當我嘗試這一點，

<bean name="propEnvironment" class="java.lang.String" id="testing"> 
    <constructor-arg value="#{ systemProperties['property.environment'] ?: systemProperties['cfg.environment'] }" /> 
</bean> 
<bean name="fullString" class="java.lang.String"> 
    <constructor-arg value="classpath:properties/#{ systemProperties['property.environment'] ?: systemProperties['cfg.environment'] }/*.properties" /> 
</bean> 
<bean class="EchoBean" lazy-init="false"> 
    <constructor-arg ref="propEnvironment" /> 
</bean> 
<bean class="EchoBean" lazy-init="false"> 
    <constructor-arg ref="fullString" /> 
</bean> 
<bean class="EchoBean" lazy-init="false"> 
    <constructor-arg value="#{@testing.toString()}" /> 
</bean> 
<bean class="EchoBean" lazy-init="false"> 
    <constructor-arg value="blah" /> 
</bean> 

使用@語法不產生任何輸出第三回聲。

2014-02-14 10:03:41,998 [main] INFO EchoBean - local 
2014-02-14 10:03:42,000 [main] INFO EchoBean - classpath:properties/local/*.properties 
2014-02-14 10:03:42,000 [main] INFO EchoBean - blah 

Answer 1

試試這個格式：

<bean class="java.net.URI" id="dbUrl"> 
    <constructor-arg value="#{systemEnvironment['DATABASE_URL']}"/> 
</bean> 

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"> 
    <property name="url" value="#{ 'jdbc:postgresql://' + @dbUrl.getHost() + ':' + @dbUrl.getPort() + @dbUrl.getPath() }"/> 
    <property name="username" value="#{ @dbUrl.getUserInfo().split(':')[0] }"/> 
    <property name="password" value="#{ @dbUrl.getUserInfo().split(':')[1] }"/> 
</bean> 

如果你對propEnvironment試圖調用toString（）？像這樣：

<encryption:encryptable-property-placeholder 
    encryptor="configurationEncryptor" 
    location="classpath:properties/#{@propEnvironment.toString()}/*.properties,classpath:properties/common.properties" />