java 在 Spring XML 配置文件中连接字符串？

Concatenate strings within a Spring XML configuration file?

提问by HDave

I have a String value in a Spring configuration file that comes to be as the result of a JNDI lookup -- it happens to be a path name:

我在 Spring 配置文件中有一个 String 值，它是 JNDI 查找的结果——它恰好是一个路径名：

<jee:jndi-lookup id="myAppHomeDir" jndi-name="myAppHomeDir" />

<jee:jndi-lookup id="myAppHomeDir" jndi-name="myAppHomeDir" />

Now I need to concatenate on to the end of this path another string and hand it off to another Spring bean as follows (which of course doesn't work):

现在我需要将另一个字符串连接到此路径的末尾，并将其传递给另一个 Spring bean，如下所示（这当然不起作用）：

<bean id="LogPath" class="org.mystuff.initBean">
    <property name="logDirectory">
       <jee:jndi-lookup id="myAppHomeDir"
                 jndi-name="myAppHomeDir" /> + "/logs"
    </property>
</bean>

Is there a simple way to do this without me having to write a utility class in Java?

有没有一种简单的方法可以做到这一点，而我不必用 Java 编写实用程序类？

回答by Grzegorz Oledzki

Try using Spring EL (expression language). I would try the following (not tested):

尝试使用Spring EL（表达式语言）。我会尝试以下（未测试）：

<jee:jndi-lookup id="myAppHomeDir" jndi-name="myAppHomeDir" />

<bean id="LogPath" class="org.mystuff.initBean">
    <property name="logDirectory" value="#{myAppHomeDir+'/logs'}"/>
</bean>

Not quite sure if it would work. The thing that troubles me is the cast from File (I guess) to String when concatenating. So if the previous one didn't work, I would try:

不太确定它是否会起作用。困扰我的是在连接时从 File（我猜）到 String 的转换。所以如果前一个不起作用，我会尝试：

#{myAppHomeDir.canonicalPath+'/logs'}

Let us know if it works.

让我们知道它是否有效。