From 9efb7ff135a3f565d7b05352e875dd6d35f048ce Mon Sep 17 00:00:00 2001
From: Jeremias Maerki <jeremias@apache.org>
Date: Thu, 27 Mar 2003 10:18:05 +0000
Subject: [PATCH] Filters can indicate whether they are ASCII filters (which
 can be disabled if the document is encrypted) Filters have a new method for
 returning a FilteredOutputStream for the new on-the-fly stream output.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@196150 13f79535-47bb-0310-9956-ffa450edef68
---
 src/java/org/apache/fop/pdf/ASCII85Filter.java  | 16 ++++++++++++++++
 src/java/org/apache/fop/pdf/ASCIIHexFilter.java | 16 ++++++++++++++++
 src/java/org/apache/fop/pdf/DCTFilter.java      |  8 ++++++++
 src/java/org/apache/fop/pdf/FlateFilter.java    | 12 +++++++++++-
 src/java/org/apache/fop/pdf/PDFFilter.java      | 17 +++++++++++++++++
 5 files changed, 68 insertions(+), 1 deletion(-)

diff --git a/src/java/org/apache/fop/pdf/ASCII85Filter.java b/src/java/org/apache/fop/pdf/ASCII85Filter.java
index fdec499bc..dcdcd5c55 100644
--- a/src/java/org/apache/fop/pdf/ASCII85Filter.java
+++ b/src/java/org/apache/fop/pdf/ASCII85Filter.java
@@ -54,6 +54,8 @@ import java.io.OutputStream;
 import java.io.InputStream;
 import java.io.IOException;
 
+import org.apache.fop.render.ps.ASCII85OutputStream;
+
 /**
  * PDF Filter for ASCII85.
  * This applies a filter to a pdf stream that converts
@@ -78,6 +80,13 @@ public class ASCII85Filter extends PDFFilter {
         return "/ASCII85Decode";
     }
 
+    /**
+     * @see org.apache.fop.pdf.PDFFilter#isASCIIFilter()
+     */
+    public boolean isASCIIFilter() {
+        return true;
+    }
+    
     /**
      * Get the decode parameters.
      *
@@ -239,4 +248,11 @@ public class ASCII85Filter extends PDFFilter {
         }
     }
 
+    /**
+     * @see org.apache.fop.pdf.PDFFilter#applyFilter(OutputStream)
+     */
+    public OutputStream applyFilter(OutputStream out) throws IOException {
+        return new ASCII85OutputStream(out);
+    }
+
 }
diff --git a/src/java/org/apache/fop/pdf/ASCIIHexFilter.java b/src/java/org/apache/fop/pdf/ASCIIHexFilter.java
index 52756d706..0e082cbe1 100644
--- a/src/java/org/apache/fop/pdf/ASCIIHexFilter.java
+++ b/src/java/org/apache/fop/pdf/ASCIIHexFilter.java
@@ -56,6 +56,8 @@ import java.io.Writer;
 import java.io.OutputStreamWriter;
 import java.io.IOException;
 
+import org.apache.fop.render.ps.ASCIIHexOutputStream;
+
 /**
  * ASCII Hex filter for PDF streams.
  * This filter converts a pdf stream to ASCII hex data.
@@ -72,6 +74,13 @@ public class ASCIIHexFilter extends PDFFilter {
         return "/ASCIIHexDecode";
     }
 
+    /**
+     * @see org.apache.fop.pdf.PDFFilter#isASCIIFilter()
+     */
+    public boolean isASCIIFilter() {
+        return true;
+    }
+    
     /**
      * Get the decode params.
      *
@@ -103,4 +112,11 @@ public class ASCIIHexFilter extends PDFFilter {
         writer.close();
     }
 
+    /**
+     * @see org.apache.fop.pdf.PDFFilter#applyFilter(OutputStream)
+     */
+    public OutputStream applyFilter(OutputStream out) throws IOException {
+        return new ASCIIHexOutputStream(out);
+    }
+
 }
diff --git a/src/java/org/apache/fop/pdf/DCTFilter.java b/src/java/org/apache/fop/pdf/DCTFilter.java
index 04af62b75..6a83c998e 100644
--- a/src/java/org/apache/fop/pdf/DCTFilter.java
+++ b/src/java/org/apache/fop/pdf/DCTFilter.java
@@ -96,5 +96,13 @@ public class DCTFilter extends PDFFilter {
         out.close();
     }
 
+    /**
+     * @see org.apache.fop.pdf.PDFFilter#applyFilter(OutputStream)
+     */
+    public OutputStream applyFilter(OutputStream out) throws IOException {
+        return out;
+        //No active filtering, OutputStream is already expected to be DCT encoded
+    }
+
 }
 
diff --git a/src/java/org/apache/fop/pdf/FlateFilter.java b/src/java/org/apache/fop/pdf/FlateFilter.java
index f830fdd09..276e3fc40 100644
--- a/src/java/org/apache/fop/pdf/FlateFilter.java
+++ b/src/java/org/apache/fop/pdf/FlateFilter.java
@@ -50,6 +50,7 @@
  */ 
 package org.apache.fop.pdf;
 
+import org.apache.fop.render.ps.FlateEncodeOutputStream;
 import org.apache.fop.util.StreamUtilities;
 
 import java.io.OutputStream;
@@ -58,7 +59,9 @@ import java.io.IOException;
 import java.util.zip.DeflaterOutputStream;
 
 /**
- * A filter to deflate a stream. Note that the attributes for
+ * A filter to deflate a stream.
+ * <p>
+ * <b>Note</b> that the attributes for
  * prediction, colors, bitsPerComponent, and columns are not supported
  * when this filter is used to handle the data compression. They are
  * only valid for externally encoded data such as that from a graphics
@@ -268,4 +271,11 @@ public class FlateFilter extends PDFFilter {
     }
 
 
+    /**
+     * @see org.apache.fop.pdf.PDFFilter#applyFilter(OutputStream)
+     */
+    public OutputStream applyFilter(OutputStream out) throws IOException {
+        return new FlateEncodeOutputStream(out);
+    }
+
 }
diff --git a/src/java/org/apache/fop/pdf/PDFFilter.java b/src/java/org/apache/fop/pdf/PDFFilter.java
index 9dba287bb..e8a18b3ff 100644
--- a/src/java/org/apache/fop/pdf/PDFFilter.java
+++ b/src/java/org/apache/fop/pdf/PDFFilter.java
@@ -110,6 +110,15 @@ public abstract class PDFFilter {
      */
     public abstract String getName();
 
+    /**
+     * Returns true if the filter is an ASCII filter that isn't necessary
+     * when encryption is active.
+     * @return boolean True if this filter is an ASCII filter
+     */
+    public boolean isASCIIFilter() {
+        return false;
+    }
+
     /**
      * return a parameter dictionary for this filter, or null
      *
@@ -127,4 +136,12 @@ public abstract class PDFFilter {
      */
     public abstract void encode(InputStream in, OutputStream out, int length) throws IOException;
 
+    /**
+     * Applies a filter to an OutputStream.
+     * @param out contents to be filtered
+     * @return OutputStream filtered contents
+     * @throws IOException In case of an I/O problem
+     */
+    public abstract OutputStream applyFilter(OutputStream out) throws IOException;
+
 }
-- 
2.39.5