Groovy example source code file (ReaderSource.java)

This example Groovy source code file (ReaderSource.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

hascleanup, hascleanup, io, ioexception, janitor, janitor, reader, reader, readersource, readersource, string

The Groovy ReaderSource.java source code

/*
 * Copyright 2003-2007 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.codehaus.groovy.control.io;

import java.io.IOException;
import java.io.Reader;

import org.codehaus.groovy.control.HasCleanup;
import org.codehaus.groovy.control.Janitor;

/**
 *  An interface for things that can supply (and potentially resupply) a Reader
 *  on a source stream.
 *
 *  @author <a href="mailto:cpoirier@dreaming.org">Chris Poirier
 *
 *  @version $Id: ReaderSource.java 6778 2007-07-02 10:40:33Z glaforge $
 */
public interface ReaderSource extends HasCleanup {
   /**
    *  Returns a new Reader on the underlying source object.  Returns
    *  null if the source can't be reopened.
    * @throws java.io.IOException if there was an error opening for stream
    * @return the reader to the resource
    */
    Reader getReader() throws IOException;
    
   /**
    *  Returns true if the source can be restarted (ie. if getReader()
    *  will return non-null on subsequent calls.
    * @return true if the resource can be reopened for reading
    */
    boolean canReopenSource();
    
   /**
    *  Returns a line from the source, or null, if unavailable.  If
    *  you supply a Janitor, resources will be cached.
    * @param lineNumber the number of the line of interest
    * @param janitor helper to clean up afterwards
    * @return the line of interest
    */
    String getLine( int lineNumber, Janitor janitor );
    
   /**
    *  Cleans up any cached resources used by getLine().
    */
    void cleanup();
}