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1
17
18 package net.sourceforge.groboutils.codecoverage.v2.ant.zip;
19
20 import java.util.Hashtable  ;
21 import java.util.Vector ;
22 import java.util.zip.ZipException ;
23
24
30 public class ExtraFieldUtils {
31
32
37 private static Hashtable implementations;
38
39 static {
40 implementations = new Hashtable ();
41 register(AsiExtraField.class);
42 }
43
44
52 public static void register(Class c) {
53 try {
54 ZipExtraField ze = (ZipExtraField) c.newInstance();
55 implementations.put(ze.getHeaderId(), c);
56 } catch (ClassCastException cc) {
57 throw new RuntimeException (c + " doesn\'t implement ZipExtraField");
58 } catch (InstantiationException ie) {
59 throw new RuntimeException (c + " is not a concrete class");
60 } catch (IllegalAccessException ie) {
61 throw new RuntimeException (c + "\'s no-arg constructor is not public");
62 }
63 }
64
65
71 public static ZipExtraField createExtraField(ZipShort headerId)
72 throws InstantiationException , IllegalAccessException {
73 Class c = (Class ) implementations.get(headerId);
74 if (c != null) {
75 return (ZipExtraField) c.newInstance();
76 }
77 UnrecognizedExtraField u = new UnrecognizedExtraField();
78 u.setHeaderId(headerId);
79 return u;
80 }
81
82
88 public static ZipExtraField[] parse(byte[] data) throws ZipException {
89 Vector v = new Vector ();
90 int start = 0;
91 while (start <= data.length - 4) {
92 ZipShort headerId = new ZipShort(data, start);
93 int length = (new ZipShort(data, start + 2)).getValue();
94 if (start + 4 + length > data.length) {
95 throw new ZipException ("data starting at " + start
96 + " is in unknown format");
97 }
98 try {
99 ZipExtraField ze = createExtraField(headerId);
100 ze.parseFromLocalFileData(data, start + 4, length);
101 v.addElement(ze);
102 } catch (InstantiationException ie) {
103 throw new ZipException (ie.getMessage());
104 } catch (IllegalAccessException iae) {
105 throw new ZipException (iae.getMessage());
106 }
107 start += (length + 4);
108 }
109 if (start != data.length) { throw new ZipException ("data starting at " + start
111 + " is in unknown format");
112 }
113
114 ZipExtraField[] result = new ZipExtraField[v.size()];
115 v.copyInto(result);
116 return result;
117 }
118
119
124 public static byte[] mergeLocalFileDataData(ZipExtraField[] data) {
125 int sum = 4 * data.length;
126 for (int i = 0; i < data.length; i++) {
127 sum += data[i].getLocalFileDataLength().getValue();
128 }
129 byte[] result = new byte[sum];
130 int start = 0;
131 for (int i = 0; i < data.length; i++) {
132 System.arraycopy(data[i].getHeaderId().getBytes(),
133 0, result, start, 2);
134 System.arraycopy(data[i].getLocalFileDataLength().getBytes(),
135 0, result, start + 2, 2);
136 byte[] local = data[i].getLocalFileDataData();
137 System.arraycopy(local, 0, result, start + 4, local.length);
138 start += (local.length + 4);
139 }
140 return result;
141 }
142
143
148 public static byte[] mergeCentralDirectoryData(ZipExtraField[] data) {
149 int sum = 4 * data.length;
150 for (int i = 0; i < data.length; i++) {
151 sum += data[i].getCentralDirectoryLength().getValue();
152 }
153 byte[] result = new byte[sum];
154 int start = 0;
155 for (int i = 0; i < data.length; i++) {
156 System.arraycopy(data[i].getHeaderId().getBytes(),
157 0, result, start, 2);
158 System.arraycopy(data[i].getCentralDirectoryLength().getBytes(),
159 0, result, start + 2, 2);
160 byte[] local = data[i].getCentralDirectoryData();
161 System.arraycopy(local, 0, result, start + 4, local.length);
162 start += (local.length + 4);
163 }
164 return result;
165 }
166 }
167 |
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