How to read all the font sizes used in a docx

I am using docx4j and the very useful webapp they've built for parts list: http://webapp.docx4java.org/OnlineDemo/PartsList.html

I have a sample document with five words. First four are in font size 12 and the last is in font size 8.

I would like to read all the different font sizes used in the document. So in this case: 12 and 8

I uploaded the sample document on the webapp and I think this information would be stored in document.xml but I'm not certain as I only see 16 but not 24 in the xml. Also, I'm not certain how to extract this information.

Questions

How can I extract font size of the word content in docx4j?
How can I extract the font color of each word and background color of the entire word document?

Solution

If the font size is not set on the run, and a style is in use, you need to check the style hierarchy. If it is not set there, it comes back to defaults.

As ECMA 4ed Part 1 puts it in 17.7.2 (Style Hierarchy):

This process can be described as follows:

First, the document defaults are applied to all runs and paragraphs in the document.

Next, the table style properties are applied to each table in the document, following the conditional formatting inclusions and exclusions specified per table.

Next, numbered item and paragraph properties are applied to each paragraph formatted with a numbering style.

Next, paragraph and run properties are applied to each paragraph as defined by the paragraph style.

Next, run properties are applied to each run with a specific character style applied.

Finally, we apply direct formatting (paragraph or run properties not from styles). If this direct formatting includes numbering, that numbering + the associated paragraph properties are applied.

If the value of the rFonts element (§17.3.2.26) references a font which is not available, applications determine a suitable alternative font via a process called font substitution, which is defined in §17.8.2.

docx4j does something like this - see for example line 430 and ff in https://github.com/plutext/docx4j/blob/master/src/main/java/org/docx4j/model/PropertyResolver.java

Similar principles apply to font color.

I don't address here how to iterate through the document word by word (or rather, run by run), other than to say google traversalutil

Example of setting font size explicitly in a run

                <w:r>
                    <w:rPr>
                        <w:sz w:val="36"/>
                    </w:rPr>
                    <w:t>this is 18 points</w:t>
                </w:r>

You can set that in Microsoft Word, or using docx4j. To see how to do it in docx4j, you can use to the webapp to generate code from a sample docx, but the essence is:

    org.docx4j.wml.R  yourRun;
    yourRun.getRPr().setSz(an HpsMeasure);