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/fonts/autodetect/NativeFontDirFinder.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: NativeFontDirFinder.java 1761020 2016-09-16 11:17:35Z ssteiner $ */

package org.apache.fop.fonts.autodetect;

import java.io.File;
import java.util.List;

/**
 * Native font finder base class
 */
public abstract class NativeFontDirFinder implements FontDirFinder {

    /**
     * Generic method used by Mac and Unix font finders.
     * @return list of natively existing font directories
     * {@inheritDoc}
     */
    public List<File> find() {
        List<File> fontDirList = new java.util.ArrayList<File>();
        String[] searchableDirectories = getSearchableDirectories();
        if (searchableDirectories != null) {
            for (String searchableDirectory : searchableDirectories) {
                File fontDir = new File(searchableDirectory);
                if (fontDir.exists() && fontDir.canRead()) {
                    fontDirList.add(fontDir);
                }
            }
        }
        return fontDirList;
    }

    /**
     * Returns an array of directories to search for fonts in.
     * @return an array of directories
     */
    protected abstract String[] getSearchableDirectories();

}

⏎ org/apache/fop/fonts/autodetect/NativeFontDirFinder.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)