集册 Java实例教程 返回给定包包含的所有文件的数组

返回给定包包含的所有文件的数组

欢马劈雪     最近更新时间:2020-01-02 10:19:05

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返回给定包包含的所有文件的数组

/*

 * Copyright (c) 2012 Data Harmonisation Panel

 * 

 * All rights reserved. This program and the accompanying materials are made

 * available under the terms of the GNU Lesser General Public License as

 * published by the Free Software Foundation, either version 3 of the License,

 * or (at your option) any later version.

 * 

 * You should have received a copy of the GNU Lesser General Public License

 * along with this distribution. If not, see <http://www.gnu.org/licenses/>.

 * 

 * Contributors:

 *     HUMBOLDT EU Integrated Project #030962

 *     Data Harmonisation Panel <http://www.dhpanel.eu>

 */

import java.io.File;

import java.io.IOException;/*来自 NowJava.com - 时代Java*/

import java.lang.reflect.Field;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.lang.reflect.Modifier;

import java.net.JarURLConnection;

import java.net.MalformedURLException;

import java.net.URI;

import java.net.URISyntaxException;

import java.net.URL;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Enumeration;

import java.util.Iterator;

import java.util.List;

import java.util.jar.JarEntry;//时代Java 提 供

import java.util.jar.JarFile;

import java.util.zip.ZipException;


public class Main{

    /**

     * The package resolver used to retrieve URLs to packages

     */

    private static PackageResolver _packageResolver = new DefaultPackageResolver();

    /**

     * Returns an array of all files contained by a given package

     * 

     * @param pkg the package (e.g. "de.igd.fhg.CityServer3D")

     * @return an array of files

     * @throws IOException if the package could not be found

     */

    public static synchronized File[] getFilesFromPackage(String pkg)

            throws IOException {


        File[] files;

        JarFile jarFile = null;

        try {

            URL u = _packageResolver.resolve(pkg);

            if (u != null && !u.toString().startsWith("jar:")) { //$NON-NLS-1$

                // we got the package as an URL. Simply create a file

                // from this URL

                File dir;

                try {

                    dir = new File(u.toURI());

                } catch (URISyntaxException e) {

                    // if the URL contains spaces and they have not been

                    // replaced by %20 then we'll have to use the following line

                    dir = new File(u.getFile());

                }

                if (!dir.isDirectory()) {

                    // try another method

                    dir = new File(u.getFile());

                }

                files = null;

                if (dir.isDirectory()) {

                    files = dir.listFiles();

                }

            } else {

                // the package may be in a jar file

                // get the current jar file and search it

                if (u != null && u.toString().startsWith("jar:file:")) { //$NON-NLS-1$

                    // first try using URL and File

                    try {

                        String p = u.toString().substring(4);

                        p = p.substring(0, p.indexOf("!/")); //$NON-NLS-1$

                        File file = new File(URI.create(p));

                        p = file.getAbsolutePath();

                        try {

                            jarFile = new JarFile(p);

                        } catch (ZipException e) {

                            throw new IllegalArgumentException(

                                    "No zip file: " + p, e); //$NON-NLS-1$

                        }

                    } catch (Throwable e1) {

                        // second try directly using path

                        String p = u.toString().substring(9);

                        p = p.substring(0, p.indexOf("!/")); //$NON-NLS-1$

                        try {

                            jarFile = new JarFile(p);

                        } catch (ZipException e2) {

                            throw new IllegalArgumentException(

                                    "No zip file: " + p, e2); //$NON-NLS-1$

                        }

                    }

                } else {

                    u = getCurrentJarURL();


                    // open jar file

                    JarURLConnection juc = (JarURLConnection) u

                            .openConnection();

                    jarFile = juc.getJarFile();

                }


                // enumerate entries and add those that match the package path

                Enumeration<JarEntry> entries = jarFile.entries();

                ArrayList<String> file_names = new ArrayList<String>();

                String package_path = pkg.replaceAll("\\.", "/"); //$NON-NLS-1$ //$NON-NLS-2$

                boolean slashed = false;

                if (package_path.charAt(0) == '/') {

                    package_path = package_path.substring(1);

                    slashed = true;

                }

                while (entries.hasMoreElements()) {

                    JarEntry j = entries.nextElement();

                    if (j.getName().matches("^" + package_path + ".+\\..+")) { //$NON-NLS-1$ //$NON-NLS-2$

                        if (slashed) {

                            file_names.add("/" + j.getName()); //$NON-NLS-1$

                        } else {

                            file_names.add(j.getName());

                        }

                    }

                }


                // convert list to array

                files = new File[file_names.size()];

                Iterator<String> i = file_names.iterator();

                int n = 0;

                while (i.hasNext()) {

                    files[n++] = new File(i.next());

                }

            }

        } catch (Throwable e) {

            throw new IOException("Could not find package: " + pkg, e); //$NON-NLS-1$

        } finally {

            if (jarFile != null) {

                jarFile.close();

            }

        }


        if (files != null && files.length == 0)

            return null; 
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