java - OutOfMemoryError while doing docx comparison using docx4j

Question

in my application i am comparing two docx files and creating one html comparison file, when i tried with below 150 or 170 lines of file then there is no issue, while i try to compare the big files like 200 lines or more than that then that time it showing the

java.lang.OutOfMemoryError: Java heap space error,

can any one please help on this?

Answer 1

You are running out of memory because you aren't using the Docx4jDriver class, which makes the diff problem more tractable by doing a paragraph level diff first.

Use it like so:

        Body newerBody = ((Document)newerPackage.getMainDocumentPart().getJaxbElement()).getBody();
        Body olderBody = ((Document)olderPackage.getMainDocumentPart().getJaxbElement()).getBody();

        // 2. Do the differencing
        java.io.StringWriter sw = new java.io.StringWriter();
        Docx4jDriver.diff( XmlUtils.marshaltoW3CDomDocument(newerBody).getDocumentElement(),
                        XmlUtils.marshaltoW3CDomDocument(olderBody).getDocumentElement(),
                           sw);

        // 3. Get the result
        String contentStr = sw.toString();
        System.out.println("Result: 

 " + contentStr);
        Body newBody = (Body) org.docx4j.XmlUtils
                        .unmarshalString(contentStr);