Copying metadata Leave feedback

GroupDocs.Metadata for Java can copy known metadata properties from one document to another. This is useful when a document is regenerated or converted and the new file has to keep the author, dates and other properties of the original.

The copyTo method works as follows:

• The operation is recursive, so it affects all nested packages as well.
• If a property exists in the destination package, its value is updated.
• If a known property is missing in the destination package, it is added.
• If a property exists only in the destination package, it is kept. Call sanitize on the destination document first if you need an exact copy.
• The source and the destination packages must be of the same type, for example both documents must be PDF files. Otherwise an exception is thrown.

1. Load the source and the destination documents
2. Get the root package of the destination document
3. Call the copyTo method of the source document
4. Save the destination document

advanced_usage.CopyToMetadata

try (Metadata sourceMetadata = new Metadata(Constants.InputPdf);
     Metadata destinationMetadata = new Metadata(Constants.CopyPdf)) {
    PdfRootPackage destinationRoot = destinationMetadata.getRootPackageGeneric();

    // Copy all known properties from the source document to the destination package
    sourceMetadata.copyTo(destinationRoot);

    System.out.println(destinationRoot.getDocumentProperties().getAuthor());
    System.out.println(destinationRoot.getDocumentProperties().getCreatedDate());
    System.out.println(destinationRoot.getDocumentProperties().getProducer());

    destinationMetadata.save(Constants.OutputPdf);
}

To copy only some of the properties, pass a list of tags to the copyTo method. Only the properties marked with at least one of the tags are copied. The method returns the number of affected properties.

try (Metadata sourceMetadata = new Metadata(Constants.InputPdf);
     Metadata destinationMetadata = new Metadata(Constants.CopyPdf)) {
    PdfRootPackage destinationRoot = destinationMetadata.getRootPackageGeneric();

    // Copy only the properties marked with the specified tags
    List<PropertyTag> tags = new ArrayList<PropertyTag>();
    tags.add(Tags.getPerson().getCreator());
    tags.add(Tags.getTime().getCreated());

    int affected = sourceMetadata.copyTo(destinationRoot, tags);
    System.out.println(String.format("Properties copied: %d", affected));

    destinationMetadata.save(Constants.OutputPdf);
}

You may easily run the code above and see the feature in action in our GitHub examples:

• GroupDocs.Metadata for .NET examples

• GroupDocs.Metadata for Java examples

Along with full featured Java library we provide simple, but powerful free Apps.

You are welcome to view and edit metadata of PDF, DOC, DOCX, PPT, PPTX, XLS, XLSX, emails, images and more with our free online Free Online Document Metadata Viewing and Editing App.