--- /dev/null
+/*
+ * 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.
+ *
+ */
+
+package org.apache.tools.zip;
+
+import java.util.Hashtable;
+import java.util.Vector;
+import java.util.zip.ZipException;
+
+/**
+ * ZipExtraField related methods
+ *
+ */
+public class ExtraFieldUtils {
+
+ /**
+ * Static registry of known extra fields.
+ *
+ * @since 1.1
+ */
+ private static Hashtable implementations;
+
+ static {
+ implementations = new Hashtable();
+ register(AsiExtraField.class);
+ register(JarMarker.class);
+ }
+
+ /**
+ * Register a ZipExtraField implementation.
+ *
+ * <p>The given class must have a no-arg constructor and implement
+ * the {@link ZipExtraField ZipExtraField interface}.</p>
+ * @param c the class to register
+ *
+ * @since 1.1
+ */
+ public static void register(Class c) {
+ try {
+ ZipExtraField ze = (ZipExtraField) c.newInstance();
+ implementations.put(ze.getHeaderId(), c);
+ } catch (ClassCastException cc) {
+ throw new RuntimeException(c + " doesn\'t implement ZipExtraField");
+ } catch (InstantiationException ie) {
+ throw new RuntimeException(c + " is not a concrete class");
+ } catch (IllegalAccessException ie) {
+ throw new RuntimeException(c + "\'s no-arg constructor is not public");
+ }
+ }
+
+ /**
+ * Create an instance of the approriate ExtraField, falls back to
+ * {@link UnrecognizedExtraField UnrecognizedExtraField}.
+ * @param headerId the header identifier
+ * @return an instance of the appropiate ExtraField
+ * @exception InstantiationException if unable to instantiate the class
+ * @exception IllegalAccessException if not allowed to instatiate the class
+ * @since 1.1
+ */
+ public static ZipExtraField createExtraField(ZipShort headerId)
+ throws InstantiationException, IllegalAccessException {
+ Class c = (Class) implementations.get(headerId);
+ if (c != null) {
+ return (ZipExtraField) c.newInstance();
+ }
+ UnrecognizedExtraField u = new UnrecognizedExtraField();
+ u.setHeaderId(headerId);
+ return u;
+ }
+
+ /**
+ * Split the array into ExtraFields and populate them with the
+ * give data.
+ * @param data an array of bytes
+ * @return an array of ExtraFields
+ * @since 1.1
+ * @throws ZipException on error
+ */
+ public static ZipExtraField[] parse(byte[] data) throws ZipException {
+ Vector v = new Vector();
+ int start = 0;
+ while (start <= data.length - 4) {
+ ZipShort headerId = new ZipShort(data, start);
+ int length = (new ZipShort(data, start + 2)).getValue();
+ if (start + 4 + length > data.length) {
+ throw new ZipException("data starting at " + start
+ + " is in unknown format");
+ }
+ try {
+ ZipExtraField ze = createExtraField(headerId);
+ ze.parseFromLocalFileData(data, start + 4, length);
+ v.addElement(ze);
+ } catch (InstantiationException ie) {
+ throw new ZipException(ie.getMessage());
+ } catch (IllegalAccessException iae) {
+ throw new ZipException(iae.getMessage());
+ }
+ start += (length + 4);
+ }
+ if (start != data.length) { // array not exhausted
+ throw new ZipException("data starting at " + start
+ + " is in unknown format");
+ }
+
+ ZipExtraField[] result = new ZipExtraField[v.size()];
+ v.copyInto(result);
+ return result;
+ }
+
+ /**
+ * Merges the local file data fields of the given ZipExtraFields.
+ * @param data an array of ExtraFiles
+ * @return an array of bytes
+ * @since 1.1
+ */
+ public static byte[] mergeLocalFileDataData(ZipExtraField[] data) {
+ int sum = 4 * data.length;
+ for (int i = 0; i < data.length; i++) {
+ sum += data[i].getLocalFileDataLength().getValue();
+ }
+ byte[] result = new byte[sum];
+ int start = 0;
+ for (int i = 0; i < data.length; i++) {
+ System.arraycopy(data[i].getHeaderId().getBytes(),
+ 0, result, start, 2);
+ System.arraycopy(data[i].getLocalFileDataLength().getBytes(),
+ 0, result, start + 2, 2);
+ byte[] local = data[i].getLocalFileDataData();
+ System.arraycopy(local, 0, result, start + 4, local.length);
+ start += (local.length + 4);
+ }
+ return result;
+ }
+
+ /**
+ * Merges the central directory fields of the given ZipExtraFields.
+ * @param data an array of ExtraFields
+ * @return an array of bytes
+ * @since 1.1
+ */
+ public static byte[] mergeCentralDirectoryData(ZipExtraField[] data) {
+ int sum = 4 * data.length;
+ for (int i = 0; i < data.length; i++) {
+ sum += data[i].getCentralDirectoryLength().getValue();
+ }
+ byte[] result = new byte[sum];
+ int start = 0;
+ for (int i = 0; i < data.length; i++) {
+ System.arraycopy(data[i].getHeaderId().getBytes(),
+ 0, result, start, 2);
+ System.arraycopy(data[i].getCentralDirectoryLength().getBytes(),
+ 0, result, start + 2, 2);
+ byte[] local = data[i].getCentralDirectoryData();
+ System.arraycopy(local, 0, result, start + 4, local.length);
+ start += (local.length + 4);
+ }
+ return result;
+ }
+}
git://source.jalview.org / vamsas.git / blobdiff