如何从BlueBoots XML的XML属性文件中读取值？

Question

How can I read values from the property file in Blueprint XML for JBoss Fuse?

Currently, I am reading like below, but I want to read from a property file. Can I use Spring BridgePropertyPlaceholoder to achieve it?

<cm:property-placeholder persistent-id="connections" update-
strategy="reload">
<cm:default-properties>
<cm:property name="xyz" value="http://xx.xx.x.x:x0x0/xxx/yyy"/>
<cm:property name="pqr" value="http://xx.xx.x.x:x0x0/xxx/yyy"/>
<cm:property name="lmn" value="mnopqr"/>
</cm:default-properties>
</cm:property-placeholder>

Answer 1

Actually, blueprint-ext and blueprint-cm that extends from it, support an external source for properties file, unrelated to the defualt ConfigAdmin used location.

It allows you to write something like:

```

  <cm:property-placeholder persistent-id="mytest"  update-strategy="reload">
<cm:location>file:///whatever/my.properties</ext:location>
  </cm:property-placeholder>

```

Se reference in blueprint-cm xsd here:

http://aries.apache.org/schemas/blueprint-cm/blueprint-cm-1.3.0.xsd

Answer 2

Your are already doing it the right way.

persistent-id indicates the name of a file in the etc/ folder of JBoss Fuse. In your case, it is etc/connections.cfg . You also have autoreload if someone edits the file.

Be aware that cfg files are property files. From: https://docs.oracle.com/javase/tutorial/essential/environment/properties.html

Properties
Properties are configuration values managed as key/value pairs . In each pair, the key and value are both String values. The key identifies, and is used to retrieve, the value, much as a variable name is used to retrieve the variable's value.

Some other specs if you want to be 100% sure: http://kajabity.com/kajabity-tools/java-properties-classes/the-java-properties-file-format/

So you are already reading a property file. Just with a different extension.

NOTE :
If you meant you want to read files scattered around the file system to configure your bundles, I strongly advise you not to do it , you're looking for troubles. Do this only if you know what you are doing and you have a reason to do it .