Question

Does anyone know what approach one can take to automatically generate Java source code, from for example an xml or json file, in eclipse?

One great example of what I am thinking of doing is what Google Android sdk does: they have an R class generated automatically from the resources.

Every time a resource file is saved in Eclipse R class is automatically regenerated.

UPDATE: Example:
In the text (xml or json file) I have the following:

 <tags>
     <tag id="ALPHA">
         <description>The first alpha tag.</description>
         <value>231232</value>
     </tag>
     <tag id="BETA">
         <description>This is the beta tag.</description>
         <value>231232</value>
     </tag>

Then in my generated java class, say R I would have something like:

R.tags.ids.ALPHA //refers to an enum value for example
R.tags.values.ALPHA //refers to final int with avlue 231232
R.tags.descriptions.ALPHA //refers to the String with description

Thanks!

Answer 1

I’m adding another answer based on your comments and also because I don’t really recommend doing this outside of Google Android Resource SDK.
Google is basically using a hierarchy of static classes (singletons) for their resources.
You need to make your XSLT generate static member variables instead of getters and setters.

I basically took my old answer and changed it to static for all member variables.
You have to be very careful doing this because I have seen so many bugs with incorrect use of the “static” modifier.

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:output method="text" />
    <xsl:template match="/" priority="100">
    public class <xsl:value-of select="name(node())" /> {
        <xsl:apply-templates  select="child::node()" />
    }
    </xsl:template>
    <xsl:template match="/*/*">
        public static String <xsl:value-of select="name()" />;
        public static String get<xsl:value-of select="name()" /> {
            return <xsl:value-of select=" name()" />;
        }

        public void static set<xsl:value-of select="name()" />(String value) {
            <xsl:value-of select="name()" /> = value;
        }
    </xsl:template>
</xsl:stylesheet>

If you process with this example XML:

<?xml version="1.0" encoding="UTF-8"?>
<Human>
    <EyeColor>brown</EyeColor>
    <HairColor>brown</HairColor>
</Human>

You get something like:
public class Human {

    public static String EyeColor;

    public static String getEyeColor {
        return EyeColor;
    }

    public static void setEyeColor(String value) {
        this.EyeColor = value;
    }


    public static String HairColor;
    public static String getHairColor {
        return HairColor;
    }

    public static void setHairColor(String value) {
        this.HairColor = value;
    }


}