external/emma 2.0.5312upstream/2.0.5312

1 files changed, 125 insertions, 0 deletions

diff --git a/core/java12/com/vladium/util/ByteArrayIStream.java b/core/java12/com/vladium/util/ByteArrayIStream.java
new file mode 100644
index 0000000..81b8d81
--- /dev/null
+++ b/core/java12/com/vladium/util/ByteArrayIStream.java
@@ -0,0 +1,125 @@
+/* Copyright (C) 2003 Vladimir Roubtsov. All rights reserved.
+ * 
+ * This program and the accompanying materials are made available under
+ * the terms of the Common Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/cpl-v10.html
+ * 
+ * $Id: ByteArrayIStream.java,v 1.1.1.1 2004/05/09 16:57:51 vlad_r Exp $
+ */
+package com.vladium.util;
+
+import java.io.InputStream;
+
+import com.vladium.util.asserts.$assert;
+
+// ----------------------------------------------------------------------------
+/**
+ * An unsynchronized version of java.io.ByteArrayInputStream.<p>
+ * 
+ * All argument validation is disabled in release mode.<p>
+ * 
+ * @author (C) 2001, Vlad Roubtsov
+ */
+public
+final class ByteArrayIStream extends InputStream
+{
+    // public: ................................................................
+
+
+    public ByteArrayIStream (final byte [] buf)
+    {
+        this (buf, buf.length);
+    }
+
+    public ByteArrayIStream (final byte [] buf, final int length)
+    {
+        if ($assert.ENABLED) $assert.ASSERT ((length >= 0) && (length <= buf.length),
+            "invalid length: " + length);
+        
+        m_buf = buf;
+        m_max = length;
+    }    
+
+    // InputStream:
+    
+    public final int read ()
+    {
+        if (m_pos >= m_max)
+            return -1;
+        else
+            return 0xFF & m_buf [m_pos ++];
+    }
+
+    public final int read (final byte [] buf, final int offset, int length)
+    {
+        if ($assert.ENABLED)
+            $assert.ASSERT ((offset >= 0) && (offset <= buf.length) &&
+                (length >= 0) && ((offset + length) <= buf.length),
+                "invalid input (" + buf.length + ", " + offset + ", " + length + ")");
+        
+        final int pos = m_pos;
+        final int max = m_max;
+        
+        if (pos >= max) return -1;
+        if (pos + length > max) length = max - pos;
+        if (length <= 0) return 0;
+        
+        final byte [] mbuf = m_buf;
+        
+        if (length < NATIVE_COPY_THRESHOLD)
+            for (int i = 0; i < length; ++ i) buf [offset + i] = mbuf [pos + i];
+        else
+            System.arraycopy (mbuf, pos, buf, offset, length);
+            
+        m_pos += length;
+        
+        return length;
+    }
+    
+    public final int available ()
+    {
+        return m_max - m_pos;
+    }
+    
+    public final long skip (long n)
+    {
+        if (m_pos + n > m_max) n = m_max - m_pos;
+
+        if (n < 0) return 0;        
+        m_pos += n;
+        
+        return n;
+    }
+    
+    /**
+     * Differs from the contruct for InputStream.reset() in that this method
+     * always resets the stream to the same it was immediately after creation.
+     */
+    public final void reset ()
+    {
+        m_pos = 0;
+    }
+
+    /**
+     * Equivalent to {@link #reset()}. 
+     */
+    public final void close ()
+    {
+        reset ();
+    }
+
+    // protected: .............................................................
+
+    // package: ...............................................................
+    
+    // private: ...............................................................
+    
+    
+    private final byte [] m_buf;
+    private final int m_max;
+    private int m_pos;
+
+    private static final int NATIVE_COPY_THRESHOLD  = 9;
+
+} // end of class
+// ----------------------------------------------------------------------------
\ No newline at end of file