Java tutorial
/** * 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 org.apache.camel.converter; import java.io.BufferedInputStream; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.UnsupportedEncodingException; import java.nio.ByteBuffer; import org.apache.camel.Converter; import org.apache.camel.Exchange; import org.apache.camel.util.IOHelper; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Some core java.nio based * <a href="http://camel.apache.org/type-converter.html">Type Converters</a> * * @version $Revision$ */ @Converter public final class NIOConverter { private static final transient Log LOG = LogFactory.getLog(NIOConverter.class); /** * Utility classes should not have a public constructor. */ private NIOConverter() { } @Converter public static byte[] toByteArray(ByteBuffer buffer) { return buffer.array(); } @Converter public static String toString(ByteBuffer buffer, Exchange exchange) throws IOException { return IOConverter.toString(buffer.array(), exchange); } @Converter public static ByteBuffer toByteBuffer(byte[] data) { return ByteBuffer.wrap(data); } @Converter public static ByteBuffer toByteBuffer(File file) throws IOException { InputStream in = null; try { byte[] buf = new byte[(int) file.length()]; in = new BufferedInputStream(new FileInputStream(file)); int sizeLeft = (int) file.length(); int offset = 0; while (sizeLeft > 0) { int readSize = in.read(buf, offset, sizeLeft); sizeLeft -= readSize; offset += readSize; } return ByteBuffer.wrap(buf); } finally { IOHelper.close(in, "Failed to close file stream: " + file.getPath(), LOG); } } @Converter public static ByteBuffer toByteBuffer(String value, Exchange exchange) { ByteBuffer buf = ByteBuffer.allocate(value.length()); byte[] bytes = null; if (exchange != null) { String charsetName = exchange.getProperty(Exchange.CHARSET_NAME, String.class); if (charsetName != null) { try { bytes = value.getBytes(charsetName); } catch (UnsupportedEncodingException e) { LOG.warn("Cannot convert the byte to String with the charset " + charsetName, e); } } } if (bytes == null) { bytes = value.getBytes(); } buf.put(bytes); return buf; } @Converter public static ByteBuffer toByteBuffer(Short value) { ByteBuffer buf = ByteBuffer.allocate(2); buf.putShort(value); return buf; } @Converter public static ByteBuffer toByteBuffer(Integer value) { ByteBuffer buf = ByteBuffer.allocate(4); buf.putInt(value); return buf; } @Converter public static ByteBuffer toByteBuffer(Long value) { ByteBuffer buf = ByteBuffer.allocate(8); buf.putLong(value); return buf; } @Converter public static ByteBuffer toByteBuffer(Float value) { ByteBuffer buf = ByteBuffer.allocate(4); buf.putFloat(value); return buf; } @Converter public static ByteBuffer toByteBuffer(Double value) { ByteBuffer buf = ByteBuffer.allocate(8); buf.putDouble(value); return buf; } @Converter public static InputStream toInputStream(ByteBuffer bufferbuffer) { return IOConverter.toInputStream(toByteArray(bufferbuffer)); } }