--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/tn5250j/encoding/builtin/CodepageConverterAdapter.java	Thu May 22 12:38:09 2014 -0700
@@ -0,0 +1,82 @@
+/**
+ * $Id$
+ * 
+ * Title: tn5250J
+ * Copyright:   Copyright (c) 2001,2009
+ * Company:
+ * @author: master_jaf
+ *
+ * Description:
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307 USA
+ *
+ */
+package org.tn5250j.encoding.builtin;
+
+import java.util.Arrays;
+
+/**
+ * Adapter class for converters using 8bit codepages.
+ * 
+ * @author master_jaf
+ */
+public abstract class CodepageConverterAdapter implements ICodepageConverter {
+	
+	private char[] codepage = null;
+	private int[] reverse_codepage = null;
+	
+	/* (non-Javadoc)
+	 * @see org.tn5250j.cp.ICodepageConverter#init()
+	 */
+	public ICodepageConverter init() {
+		codepage = getCodePage();
+		
+		int size = 0;
+		for (int i=0; i<codepage.length; i++) {
+			size = Math.max(size, codepage[i]);
+		}
+		assert (size + 1) < 1024*1024; // some kind of maximum size limiter.
+		reverse_codepage = new int[size+1];
+		Arrays.fill(reverse_codepage, '?');
+		for (int i=0; i<codepage.length; i++) {
+			reverse_codepage[codepage[i]] = i;
+		}
+		return this;
+	}
+	
+	/* (non-Javadoc)
+	 * @see org.tn5250j.cp.ICodepageConverter#uni2ebcdic(char)
+	 */
+	public byte uni2ebcdic(char index) {
+		assert index < reverse_codepage.length;
+		return (byte)reverse_codepage[index];
+	}
+	
+	/* (non-Javadoc)
+	 * @see org.tn5250j.cp.ICodepageConverter#ebcdic2uni(int)
+	 */
+	public char ebcdic2uni(int index) {
+		index = index & 0xFF;
+		assert index < 256;
+		return codepage[index];
+	}
+
+	/**
+	 * @return The oringal 8bit codepage. 
+	 */
+	protected abstract char[] getCodePage();
+	
+}