/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 groovy.lang;
import java.io.IOException;
import java.io.Writer;
/**
* Represents an object which is capable of writing itself to a text stream
* in a more efficient format than just creating a toString() representation
* of itself. This mechanism is particularly useful for templates and such like.
* <p>
* It is worth noting that writable implementations often override their
* toString() implementation as well to allow rendering the same result
* directly to a String; however this is not required.
*
* @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
*/
public interface Writable {
/**
* Writes this object to the given writer.
* <p>
* This is used to defer content creation until the point when it is
* streamed to the output destination. Oftentimes, content will be defined
* but not necessarily created (as is may be the case with a Closure
* definition.) In that case, the output is then 'deferred' to the point
* when it is serialized to the writer. This class may be used whenever an
* object should be responsible for creating its own textual representation,
* but creating the entire output as a single String would be inefficient
* (such as outputting a multi-gigabyte XML document.)
*
* @param out the Writer to which this Writable should output its data.
* @return the Writer that was passed
* @throws IOException if an error occurred while outputting data to the writer
*/
Writer writeTo(Writer out) throws IOException;
}