--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/plparser/PLCharScannerImpl.java	Thu Sep 02 11:55:56 2010 +0900
@@ -0,0 +1,100 @@
+package plparser;
+
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.nio.CharBuffer;
+
+public abstract class PLCharScannerImpl<Node> extends PLScannerImpl<Node> {
+
+	public CharBuffer cb;
+
+
+	public PLCharScannerImpl(PLScanner<Node> plScannerImpl, Dictionary<Node> dict,
+			Token<Node> nullToken) {
+		super(plScannerImpl, dict, nullToken);
+	}
+
+	public PLCharScannerImpl() {
+		super();
+	}
+
+	public Token<Node> lookupDict(CharBuffer w, TokenID id) {
+		Token<Node> t;
+		String s = w.flip().toString();
+		if ((t = dict.get(s))==null) {
+			dict.put(s, t = new Token<Node>(s,id));
+		}
+		return nextToken = t;
+	}
+
+	public char nextChar() {
+		if (!cb.hasRemaining()) extendInput();
+		char ch = cb.get();
+		if (ch=='\n') lineno++;
+		return ch;
+	}
+
+	@Override
+	public boolean hasRemaining() {
+		return cb.hasRemaining()||extendInput();
+	}
+
+	protected boolean extendInput() {
+		if (file!=null && cb.position()!=0) {
+			// move remaining data to the top, set position for next read
+			cb.compact();
+			try {
+				if (prompt!=null) System.out.print(prompt);
+				if (file.read(cb)>0) {
+					cb.flip();    // prepare for get
+					return true;
+				} else {
+					throw new IOException();
+				}
+			} catch (IOException e) {
+				file = null ; 
+				cb.flip();
+			}
+		}
+		return false;
+	}
+
+	@Override
+	public PLScanner<Node> set(String exp) {
+		cb = CharBuffer.wrap(exp);
+		filename = null; file = null;
+		nextToken = nullToken;
+		return this;
+	}
+
+	@Override
+	public PLScanner<Node> setFile(String file) throws FileNotFoundException {
+		this.filename = file;
+		nextToken = nullToken;
+		set(new FileReader(file));
+		return this;
+	}
+
+	@Override
+	public PLScanner<Node> set(InputStreamReader file) {
+		this.file = file;
+		cb = CharBuffer.allocate(BufferSize);
+		try {
+			if (prompt!=null) System.out.print(prompt);
+			if (file.read(cb) <= 0) {
+				throw new IOException();
+			}
+		} catch (IOException e) {
+			file = null; cb = null;
+			set("");
+			return this;
+		} finally {
+			cb.flip();
+		}
+		lineno = 0;
+		return this;
+	}
+
+}
\ No newline at end of file