Accessing resource data from JCR repo

Question

Using sling resource interface I am trying to get access the data saved as a binary property to my JCR node. Currently I am doing it in the following ways , which is returning me a null value.

Resource dataResource = resourceResolver.getResource("/testNode/A/test.txt");
ValueMap properties = dataResource.adaptTo(ValueMap.class);        

String expected = properties.get("jcr:data").toString(); // null
InputStream content = (InputStream) actualProp.get("jcr:data");  // null

Can anyone let me know what is missing , or what is the best way to read the jcr:data property , which is present as a binary data. The dataResource is a nt:unstructured one.

the output it shows is :- org.apache.sling.jcr.resource.internal.helper.LazyInputStream@4f4c8085

Sorry, but could you let me ask you a question? Did you try my code yet? How about the result? Thank you so much! — Tuna, Jun 06 '13 at 18:22

score 12 · Answer 1 · answered Jun 10 '13 at 08:23

You mention that you were using the Sling resource API rather than the JCR API. You can adapt the resource to an InputStream directly from a Resource like so:

Resource dataResource = resourceResolver.getResource("/testNode/A/test.txt/jcr:content");
InputStream is = dataResource.adaptTo(InputStream.class);

As long as the resource is an nt:file or nt:resource, the contents of the jcr:data attribute should be returned as an InputStream.

From there you can read from the InputStream as Tuan suggested in his answer.

You can see an example of this functionality from the following unit test: http://svn.apache.org/repos/asf/sling/whiteboard/fmeschbe/resource/jcr.resource/src/test/java/org/apache/sling/jcr/resource/internal/helper/jcr/JcrNodeResourceTest.java

i tried without the jcr:content and i am able to get the resource. . — Jianhong, May 26 '14 at 10:00

score 1 · Answer 2 · answered Jun 05 '13 at 07:54

1

If I remember correctly, your path should be more like:

Resource dataResource = resourceResolver.getResource("/testNode/A/test.txt/jcr:content");

I would personally adapt that resource to a JCR Node (javax.jcr.Node) and use JCR API from there (#getProperty(), #getBinary()), but that may be my old school upbringing speaking.

answered Jun 05 '13 at 07:54

Jan Kuźniak

308
1
4

No , actually test.txt is itself a **nt:unstructured node** , to which its all metadata has been set as its properties. The file content is also present as a property of it in binarydata form , which i wants to read. Hope it makes some sense now. – Raja Jun 05 '13 at 08:39
Ah, sorry, no idea why assumed it's an *nt:file*. Did you try using JCR API anyway? – Jan Kuźniak Jun 05 '13 at 11:31
No I am using sling's resource API for the purpose. – Raja Jun 05 '13 at 12:09

score 1 · Answer 3 · edited May 23 '17 at 11:53

1

The below code has worked for me:

import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

import javax.jcr.Node;
import javax.jcr.RepositoryException;
import javax.jcr.Session;

//skip here

Session session = (Session) resourceResolver.adaptTo(Session.class);
Node root = session.getRootNode();
Node jcrContent = root.getNode("testNode/A/test.txt/jcr:content");

InputStream is = jcrContent.getProperty("jcr:data").getBinary().getStream();

BufferedInputStream bis = new BufferedInputStream(is);
ByteArrayOutputStream buf = new ByteArrayOutputStream();
int result = bis.read();
while (result != -1) {
    byte b = (byte) result;
    buf.write(b);
    result = bis.read();
}

System.out.println("plain text: " + buf.toString());

Also you can find more information at another post

edited May 23 '17 at 11:53

Community

1
1

answered Jun 05 '13 at 18:33

Tuna

2,937
4
37
61

2

You should keep a reference to your Binary object to close it when you're done. – ehsavoie Jun 06 '13 at 06:03
@ehsavoie Are you talking about `InputStream is`? – Tuna Jun 06 '13 at 11:36
thanks , it worked well , but only after adapting the resource to a JCR Node (javax.jcr.Node) and using JCR API , which actually I was not intended to do. – Raja Jun 07 '13 at 05:14
I will try to do it with Sling API :) – Tuna Jun 07 '13 at 06:53

score 0 · Answer 4 · answered Jun 04 '19 at 16:52

In AEM, files are often stored as assets. If that is the case, you can adapt the respective resource (the one with dam:Asset as primary type) to an asset and read from the file in the following way:

InputStream inputStream = resource.adaptTo(Asset.class).getOriginal().getStream()

Tuan Dang's method works, but all of the JCR Node methods throw RepositoryException.

Baeldung has a summary on how to convert input stream to a string.

Accessing resource data from JCR repo

4 Answers4