Fix bug #52665 - When reading from a ZipFileZipEntrySource that has already been closed, give IllegalArgumentException rather than NPE

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1244450 13f79535-47bb-0310-9956-ffa450edef68

src/documentation/content/xdocs/status.xml

@@ -34,6 +34,7 @@
 
     <changes>
         <release version="3.8-beta6" date="2012-??-??">
+           <action dev="poi-developers" type="fix">52665 - When reading from a ZipFileZipEntrySource that has already been closed, give IllegalArgumentException rather than NPE</action>
            <action dev="poi-developers" type="fix">52664 - MAPIMessage may not always have name chunks when checking for 7 bit encodings</action>
            <action dev="poi-developers" type="fix">52649 - fixed namespace issue in WordToFoConverter</action>
            <action dev="poi-developers" type="fix">52385 - avoid trancated array and vector data when reading OLE properties</action>

src/ooxml/java/org/apache/poi/openxml4j/util/ZipFileZipEntrySource.java

@@ -41,10 +41,16 @@ public class ZipFileZipEntrySource implements ZipEntrySource {
    }
 
    public Enumeration<? extends ZipEntry> getEntries() {
+      if (zipArchive == null)
+         throw new IllegalStateException("Zip File is closed");
+      
       return zipArchive.entries();
    }
 
    public InputStream getInputStream(ZipEntry entry) throws IOException {
+      if (zipArchive == null)
+         throw new IllegalStateException("Zip File is closed");
+      
       return zipArchive.getInputStream(entry);
    }
 }