Only calculate the CRC of STORED entries in <zip> if absolutely necessary.

PR: 21899


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@275010 13f79535-47bb-0310-9956-ffa450edef68

WHATSNEW

@@ -548,6 +548,9 @@ If set to true, the process will be spawned. Bugzilla Report 5907.
   <parallel> to throw an exception if any thread fails without
   waiting for all other threads to complete.
 
+* <zip> and friends will consume far less memory than they used to
+  when run with compress="false".  Bugzilla Report 21899.
+
 Changes from Ant 1.5.2 to Ant 1.5.3
 ===================================
 

docs/external.html

@@ -3891,6 +3891,43 @@
       valign="top" align="left">
           Commercial
       </td>
+      </tr>
+        </table>
+                                                    <h4 class="subsection">
+        <a name="Zelix KlassMaster Java Obfuscator"></a>
+        Zelix KlassMaster Java Obfuscator
+      </h4>
+                        <p>The task ZKMTask allows the Zelix KlassMaster Java obfuscator to be integrated into an Ant build.</p>
+                                      <table class="externals" cellspacing="1" cellpadding="4">
+              <tr>
+                      <th colspan="1" rowspan="1"
+      valign="top" align="left">
+          Compatibility:
+      </th>
+                          <td colspan="1" rowspan="1"
+      valign="top" align="left">
+          Ant 1.4.1
+      </td>
+      </tr>
+                  <tr>
+                      <th colspan="1" rowspan="1"
+      valign="top" align="left">
+          URL:
+      </th>
+                          <td colspan="1" rowspan="1"
+      valign="top" align="left">
+          <a href="http://www.zelix.com/klassmaster/docs/buildToolApi.html">Zelix KlassMaster Ant Task</a>
+      </td>
+      </tr>
+                  <tr>
+                      <th colspan="1" rowspan="1"
+      valign="top" align="left">
+          License:
+      </th>
+                          <td colspan="1" rowspan="1"
+      valign="top" align="left">
+          Commercial
+      </td>
       </tr>
         </table>
                               

src/etc/testcases/taskdefs/unzip.xml

@@ -27,6 +27,12 @@
     <ant antfile="zip.xml" target="cleanup" />
   </target>
 
+  <target name="testUncompressedZipTask">
+    <ant antfile="zip.xml" target="uncompressed-feather" />
+    <unzip src="asf-logo.gif.zip" dest="." />
+    <ant antfile="zip.xml" target="cleanup" />
+  </target>
+
   <target name="realTest">
     <unzip src="expected/asf-logo.gif.zip" dest="." />
   </target>

src/etc/testcases/taskdefs/zip.xml

@@ -55,6 +55,12 @@
          includes="asf-logo.gif" />
   </target>
 
+  <target name="uncompressed-feather">
+    <zip destFile="asf-logo.gif.zip"
+         basedir=".."
+         includes="asf-logo.gif" compress="false"/>
+  </target>
+
   <!-- legacy attribute support -->
   <target name="test8">
     <zip zipfile="test8.zip" basedir="." >

src/main/org/apache/tools/ant/taskdefs/Zip.java

@@ -977,15 +977,11 @@ public class Zip extends MatchingTask {
             /*
             * ZipOutputStream.putNextEntry expects the ZipEntry to
             * know its size and the CRC sum before you start writing
-            * the data when using STORED mode.
+            * the data when using STORED mode - unless it is seekable.
             *
             * This forces us to process the data twice.
-            *
-            * In DEFLATED mode, it will take advantage of a Zip
-            * Version 2 feature where size can be stored after the
-            * data (as the data itself signals end of data).
             */
-            if (!doCompress) {
+            if (!zOut.isSeekable() && !doCompress) {
                 long size = 0;
                 CRC32 cal = new CRC32();
                 if (!in.markSupported()) {

src/main/org/apache/tools/zip/ZipOutputStream.java

@@ -80,12 +80,12 @@ import java.util.zip.ZipException;
  * file.</p>
  *
  * <p>If RandomAccessFile cannot be used, this implementation will use
- * a Data Descriptor to store size and
- * CRC information for DEFLATED entries, this means, you don't need to
+ * a Data Descriptor to store size and CRC information for {@link
+ * #DEFLATED DEFLATED} entries, this means, you don't need to
  * calculate them yourself.  Unfortunately this is not possible for
- * the STORED method, here setting the CRC and uncompressed size
- * information is required before {@link #putNextEntry putNextEntry}
- * will be called.</p>
+ * the {@link #STORED STORED} method, here setting the CRC and
+ * uncompressed size information is required before {@link
+ * #putNextEntry putNextEntry} can be called.</p>
  *
  * @author Stefan Bodewig
  * @author Richard Evans
@@ -290,6 +290,20 @@ public class ZipOutputStream extends FilterOutputStream {
         }
     }
 
+    /**
+     * Is this archive writing to a seekable stream (i.e. a random
+     * access file)?
+     *
+     * <p>For seekable streams, you don't need to calculate the CRC or
+     * uncompressed size for {@link #STORED STORED} entries before
+     * invoking {@link #putEntry putEntry}.
+     *
+     * @since 1.17
+     */
+    public boolean isSeekable() {
+        return raf != null;
+    }
+
     /**
      * The encoding to use for filenames and the file comment.
      *

src/testcases/org/apache/tools/ant/taskdefs/UnzipTest.java

@@ -101,6 +101,13 @@ public class UnzipTest extends BuildFileTest {
                                            project.resolveFile("asf-logo.gif")));
     }
     
+    public void testTestUncompressedZipTask() throws java.io.IOException {
+        FileUtils fileUtils = FileUtils.newFileUtils();
+        executeTarget("testUncompressedZipTask");
+        assertTrue(fileUtils.contentEquals(project.resolveFile("../asf-logo.gif"),
+                                           project.resolveFile("asf-logo.gif")));
+    }
+    
     /*
      * PR 11100
      */