IO-152 - Add ByteArrayOutputStream.write(InputStream)

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/io/trunk@609421 13f79535-47bb-0310-9956-ffa450edef68

Author: jukka

src/java/org/apache/commons/io/output/ByteArrayOutputStream.java

@@ -17,6 +17,7 @@
 package org.apache.commons.io.output;
 
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.UnsupportedEncodingException;
 import java.util.ArrayList;
@@ -172,6 +173,34 @@ public synchronized void write(int b) {
         count++;
     }
 
+    /**
+     * Writes the entire contents of the specified input stream to this
+     * byte stream. Bytes from the input stream are read directly into the
+     * internal buffers of this streams.
+     *
+     * @param in the input stream to read from
+     * @return total number of bytes read from the input stream
+     *         (and written to this stream)
+     * @throws IOException if an I/O error occurs while reading the input stream
+     * @since Commons IO 1.4
+     */
+    public synchronized int write(InputStream in) throws IOException {
+        int readCount = 0;
+        int inBufferPos = count - filledBufferSum;
+        int n = in.read(currentBuffer, inBufferPos, currentBuffer.length - inBufferPos);
+        while (n != -1) {
+            readCount += n;
+            inBufferPos += n;
+            count += n;
+            if (inBufferPos == currentBuffer.length) {
+                needNewBuffer(currentBuffer.length);
+                inBufferPos = 0;
+            }
+            n = in.read(currentBuffer, inBufferPos, currentBuffer.length - inBufferPos);
+        }
+        return readCount;
+    }
+
     /**
      * @see java.io.ByteArrayOutputStream#size()
      */

src/test/org/apache/commons/io/output/ByteArrayOutputStreamTestCase.java

@@ -16,6 +16,7 @@
  */
 package org.apache.commons.io.output;
 
+import java.io.ByteArrayInputStream;
 import java.io.IOException;
 
 import junit.framework.TestCase;
@@ -120,7 +121,13 @@ public void testStream() throws Exception {
         written = writeData(baout, ref, new int[] {5, 47, 33, 60, 1, 0, 8});
         assertEquals(155, written);
         checkStreams(baout, ref);
-        
+
+        //Test the readFrom(InputStream) method
+        baout.reset();
+        written = baout.write(new ByteArrayInputStream(ref.toByteArray()));
+        assertEquals(155, written);
+        checkStreams(baout, ref);
+
         //Write the commons Byte[]OutputStream to a java.io.Byte[]OutputStream 
         //and vice-versa to test the writeTo() method.
         ByteArrayOutputStream baout1 = new ByteArrayOutputStream(32);