doc/ReaderUtil.java

/*
 * 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.
 */

/*
 * This file is one of the source files for the examples contained in
 * /src/site/xdoc/examples.xml
 * It is not intended to be included in a source release.
 */

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

import org.apache.commons.pool2.ObjectPool;

/**
 * Maintains a pool of StringBuffers used to dump contents of Readers.
 */
public class ReaderUtil {

    private ObjectPool<StringBuffer> pool;

    public ReaderUtil(ObjectPool<StringBuffer> pool) {
        this.pool = pool;
    }

    /**
     * Dumps the contents of the {@link Reader} to a String, closing the {@link Reader} when done.
     */
    public String readToString(Reader in)
        throws IOException {
        StringBuffer buf = null;
        try {
            buf = pool.borrowObject();
            for (int c = in.read(); c != -1; c = in.read()) {
                buf.append((char) c);
            }
            return buf.toString();
        } catch (IOException e) {
            throw e;
        } catch (Exception e) {
            throw new RuntimeException("Unable to borrow buffer from pool" + e.toString());
        } finally {
            try {
                in.close();
            } catch (Exception e) {
                // ignored
            }
            try {
                if (null != buf) {
                    pool.returnObject(buf);
                }
            } catch (Exception e) {
                // ignored
            }
        }
    }
}