ai.api.util.IOUtils Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of libai
API.AI Java SDK allows using voice commands and integration with dialog scenarios defined for a particular agent in API.AI.
There is a newer version: 1.6.12
Show newest version
package ai.api.util;

/***********************************************************************************************************************
 *
 * API.AI Java SDK - client-side libraries for API.AI
 * =================================================
 *
 * Copyright (C) 2017 by Speaktoit, Inc. (https://www.speaktoit.com) https://www.api.ai
 *
 ***********************************************************************************************************************
 *
 * 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.
 *
 ***********************************************************************************************************************/

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.Reader;
import java.io.StringWriter;
import java.io.Writer;
import java.nio.charset.Charset;

/**
 * Small subset of IO helping functions
 */
public class IOUtils {

  private static final int DEFAULT_BUFFER_SIZE = 4096;
  private static final String DEFAULT_CHARSET = "UTF-8";

  /**
   * Write string to byte stream
   * 
   * @param data Source string
   * @param outputStream Output stream
   * @param charset Convert string to bytes according to given {@link Charset}
   * @throws IOException
   */
  public static void writeAll(String data, OutputStream outputStream, Charset charset)
      throws IOException {
    writeAll(data, outputStream, charset.name());
  }

  /**
   * Write string to byte stream
   * 
   * @param data Source string
   * @param outputStream Output stream
   * @param charset Convert string to bytes according to given
   * @throws IOException
   */
  public static void writeAll(String data, OutputStream outputStream, String charset)
      throws IOException {
    if ((data != null) && (data.length() > 0)) {
      outputStream.write(data.getBytes(charset));
    }
  }

  /**
   * Write string to byte stream
   * 
   * @param data Source string
   * @param outputStream Output stream
   * @throws IOException
   */
  public static void writeAll(String data, OutputStream outputStream) throws IOException {
    writeAll(data, outputStream, DEFAULT_CHARSET);
  }

  /**
   * Read all stream byte data into {@link String}
   * 
   * @param inputStream Source stream
   * @param charset Convert bytes to chars according to given {@link Charset}
   * @return Empty {@link String} if there was no data in stream
   * @throws IOException
   */
  public static String readAll(InputStream inputStream, Charset charset) throws IOException {
    return readAll(inputStream, charset.name());
  }

  /**
   * Read all stream byte data into {@link String}
   * 
   * @param inputStream Source stream
   * @param charset Convert bytes to chars according to given
   * @return Empty {@link String} if there was no data in stream
   * @throws IOException
   */
  public static String readAll(InputStream inputStream, String charset) throws IOException {
    try (InputStreamReader streamReader = new InputStreamReader(inputStream, charset)) {
      return readAll(streamReader);
    }
  }

  /**
   * Read all stream byte data into {@link String}
   * 
   * @param inputStream Source stream
   * @return Empty {@link String} if there was no data in stream
   * @throws IOException
   */
  public static String readAll(InputStream inputStream) throws IOException {
    return readAll(inputStream, DEFAULT_CHARSET);
  }

  /**
   * Read all chars into String
   * 
   * @param streamReader Input stream reader
   * @return Empty {@link String} if there was no data in stream
   * @throws IOException
   */
  public static String readAll(InputStreamReader streamReader) throws IOException {
    StringWriter result = new StringWriter();
    copy(streamReader, result);
    return result.toString();
  }

  private static long copy(Reader reader, Writer writer) throws IOException {
    return copy(reader, writer, new char[DEFAULT_BUFFER_SIZE]);
  }

  private static long copy(Reader reader, Writer writer, char[] buffer) throws IOException {
    assert buffer != null;
    assert buffer.length > 0;

    long result = 0;

    int read = reader.read(buffer);

    while (read > 0) {
      writer.write(buffer, 0, read);
      result += read;
      read = reader.read(buffer);
    }

    return result;
  }

}