What Is fop.jar? I got it from the fop-2.7-bin.zip.

fop.jar in fop-2.7-bin.zip is the JAR file for FOP 2.7, which is a print formatter driven by XSL formatting objects (XSL-FO). You can obtain fop.jar from the build folder of the fop-2.7-bin.zip file.

Below is the information about the fop.jar (2.2) file:

JAR File Size and Download Location:

JAR name: fop.jar, fop-2.7.jar
Target JDK version: 1.7
File name: fop.jar
File size: 4442817 bytes
Release date: 20-Jan-2022
Download: Apache FOP Website

Java source code files for fop.jar:

⏎ org/apache/fop/render/afp/extensions/AFPPageOverlay.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/* $Id: AFPPageOverlay.java 1895653 2021-12-07 08:18:20Z ssteiner $ */

package org.apache.fop.render.afp.extensions;

import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;

import static org.apache.fop.render.afp.extensions.AFPPageOverlayElement.ATT_X;
import static org.apache.fop.render.afp.extensions.AFPPageOverlayElement.ATT_Y;

/**
 * This extension allows to include an AFP Page Overlay resource. It is implemented as an extension
 * attachment ({@link org.apache.fop.fo.extensions.ExtensionAttachment}).
 */
public class AFPPageOverlay extends AFPExtensionAttachment {

    private static final long serialVersionUID = 8548056652642588919L;

    /**
     * The x coordinate
     */
    private int x;

    /**
     * The y coordinate
     */
    private int y;

    /**
     * Default constructor.
     */
    public AFPPageOverlay() {
        super(AFPElementMapping.INCLUDE_PAGE_OVERLAY);
    }

    /**
     * returns X coordinate
     * @return x integer
     */
    public int getX() {
        return x;
    }

    /**
     * Sets the X coordinate
     * @param x The integer to be set.
     */
    public void setX(int x) {
        this.x = x;
    }

    /**
     * returns Y coordinate
     * @return y integer
     */
    public int getY() {
        return y;
    }

    /**
     * Sets the Y coordinate
     * @param y The integer to be set.
     */
    public void setY(int y) {
        this.y = y;
    }

    /** {@inheritDoc} */
    public void toSAX(ContentHandler handler) throws SAXException {
        AttributesImpl atts = new AttributesImpl();
        if (name != null && name.length() > 0) {
            atts.addAttribute("", ATT_NAME, ATT_NAME, "CDATA", name);
        }
        atts.addAttribute(null, ATT_X, ATT_X, "CDATA", String.valueOf(x));
        atts.addAttribute(null, ATT_Y, ATT_Y, "CDATA", String.valueOf(y));
        handler.startElement(CATEGORY, elementName, elementName, atts);
        handler.endElement(CATEGORY, elementName, elementName);
    }

    /** {@inheritDoc} */
    public String toString() {
        return getClass().getName() + "(element-name=" + getElementName()
            + " name=" + getName() + " x=" + getX() + " y=" + getY() + ")";
    }
}

⏎ org/apache/fop/render/afp/extensions/AFPPageOverlay.java

Or download all of them as a single archive file:

File name: fop-2.7-src.zip
File size: 3401312 bytes
Release date: 2022-01-20
Download 

⇒ "fop" Command in fop-2.7-bin.zip

⇐ What Is fop-2.7-bin.zip

⇑ Download and Installing of FOP 2.x

⇑⇑ FAQ for FOP (Formatting Object Processor)