fileentry.java

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/**
 * @(#)FileEntry.java	1.12 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.tools.javac.v8.util;
import java.util.zip.*;

import java.io.*;


/**
 * A class that abstracts from the differences between Files and ZipEntries.
 */
public abstract class FileEntry {

    public FileEntry() {
        super();
    }

    /**
      * Same functionality as File.open().
      */
    public abstract InputStream open() throws IOException;

            /**
             * Same functionality as File.getName().
             */
            public abstract String getName();

            /**
             * Same functionality as File.getPath().
             */
            public abstract String getPath();

            /**
             * Same functionality as File.length().
             */
            public abstract long length();

            /**
             * Same functionality as File.toString().
             */
    public String toString() {
        return getName();
    }

    /**
      * An `undetermined' value for the `lastmod' modification date cache.
      */
    private static final int UNDET = -2;

    /**
     * A cache for the modification date returned by lastModified().
     */
    private long lastmod = UNDET;

    /**
     * To be defined in subclass; same functionality
     *  as File.lastModified().
     */
    abstract long lastMod();

    /**
     * Same functionality as File.lastModified()
     */
    public long lastModified() {
        if (lastmod == UNDET)
            lastmod = lastMod();
        return lastmod;
    }

    /**
      * A subclass of FileEntry representing regular files.
      */
    public static class Regular extends FileEntry {

        /**
         * The file's name.
         */
        private String name;

        /**
         * The underlying file.
         */
        File f;

        public Regular(String name, File f) {
            super();
            this.name = name;
            this.f = f;
        }

        public InputStream open() throws IOException {
            return new FileInputStream(f);
        }

        public String getName() {
            return name;
        }

        public String getPath() {
            return f.getPath();
        }

        public long length() {
            return f.length();
        }

        long lastMod() {
            return f.lastModified();
        }
    }

    /**
      * A subclass of FileEntry representing zip entries.
      */
    public static class Zipped extends FileEntry {

        /**
         * The entry's name.
         */
        private String name;

        /**
         * The zipfile containing the entry.
         */
        ZipFile zdir;

        /**
         * The underlying zip entry object.
         */
        ZipEntry entry;

        public Zipped(String name, ZipFile zdir, ZipEntry entry) {
            super();
            this.name = name;
            this.zdir = zdir;
            this.entry = entry;
        }

        public InputStream open() throws IOException {
            return zdir.getInputStream(entry);
        }

        public String getName() {
            return name;
        }

        public String getPath() {
            return zdir.getName() + "(" + entry.toString() + ")";
        }

        public long length() {
            return entry.getSize();
        }

        long lastMod() {
            return entry.getTime();
        }
    }
}