Convert the specified CharSequence to an input stream, encoded as bytes using the default character encoding of the platform. - Android File Input Output

Android examples for File Input Output:InputStream

Description

Convert the specified CharSequence to an input stream, encoded as bytes using the default character encoding of the platform.

Demo Code

/*//from  w  w  w  . j a  v  a  2  s.  com
 * 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.
 */
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.CharArrayWriter;
import java.io.Closeable;
import java.io.EOFException;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Reader;
import java.io.Writer;
import java.net.Socket;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

public class Main{
    /**
     * The default buffer size to use for {@link #copyLarge(InputStream, OutputStream)} and {@link #copyLarge(Reader, Writer)}
     */
    private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;
    /**
     * Convert the specified CharSequence to an input stream, encoded as bytes using the default character encoding of the platform.
     * 
     * @param input
     *          the CharSequence to convert
     * @return an input stream
     * @since Commons IO 2.0
     */
    public static InputStream toInputStream(CharSequence input) {
        return toInputStream(input.toString());
    }
    /**
     * Convert the specified CharSequence to an input stream, encoded as bytes using the specified character encoding.
     * <p>
     * Character encoding names can be found at <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
     * 
     * @param input
     *          the CharSequence to convert
     * @param encoding
     *          the encoding to use, null means platform default
     * @throws IOException
     *           if the encoding is invalid
     * @return an input stream
     * @since Commons IO 2.0
     */
    public static InputStream toInputStream(CharSequence input,
            String encoding) throws IOException {
        return toInputStream(input.toString(), encoding);
    }
    /**
     * Convert the specified string to an input stream, encoded as bytes using the default character encoding of the platform.
     * 
     * @param input
     *          the string to convert
     * @return an input stream
     * @since Commons IO 1.1
     */
    public static InputStream toInputStream(String input) {
        byte[] bytes = input.getBytes();
        return new ByteArrayInputStream(bytes);
    }
    /**
     * Convert the specified string to an input stream, encoded as bytes using the specified character encoding.
     * <p>
     * Character encoding names can be found at <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
     * 
     * @param input
     *          the string to convert
     * @param encoding
     *          the encoding to use, null means platform default
     * @throws IOException
     *           if the encoding is invalid
     * @return an input stream
     * @since Commons IO 1.1
     */
    public static InputStream toInputStream(String input, String encoding)
            throws IOException {
        byte[] bytes = encoding != null ? input.getBytes(encoding) : input
                .getBytes();
        return new ByteArrayInputStream(bytes);
    }
    /**
     * Get the contents of an <code>InputStream</code> as a String using the default character encoding of the platform.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
     * 
     * @param input
     *          the <code>InputStream</code> to read from
     * @return the requested String
     * @throws NullPointerException
     *           if the input is null
     * @throws IOException
     *           if an I/O error occurs
     */
    public static String toString(InputStream input) throws IOException {
        StringBuilderWriter sw = new StringBuilderWriter();
        copy(input, sw);
        return sw.toString();
    }
    /**
     * Get the contents of an <code>InputStream</code> as a String using the specified character encoding.
     * <p>
     * Character encoding names can be found at <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
     * 
     * @param input
     *          the <code>InputStream</code> to read from
     * @param encoding
     *          the encoding to use, null means platform default
     * @return the requested String
     * @throws NullPointerException
     *           if the input is null
     * @throws IOException
     *           if an I/O error occurs
     */
    public static String toString(InputStream input, String encoding)
            throws IOException {
        StringBuilderWriter sw = new StringBuilderWriter();
        copy(input, sw, encoding);
        return sw.toString();
    }
    /**
     * Get the contents of a <code>Reader</code> as a String.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedReader</code>.
     * 
     * @param input
     *          the <code>Reader</code> to read from
     * @return the requested String
     * @throws NullPointerException
     *           if the input is null
     * @throws IOException
     *           if an I/O error occurs
     */
    public static String toString(Reader input) throws IOException {
        StringBuilderWriter sw = new StringBuilderWriter();
        copy(input, sw);
        return sw.toString();
    }
    /**
     * Copy bytes from an <code>InputStream</code> to an <code>OutputStream</code>.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
     * <p>
     * Large streams (over 2GB) will return a bytes copied value of <code>-1</code> after the copy has completed since the correct number of bytes cannot be returned as an int. For large streams use the <code>copyLarge(InputStream, OutputStream)</code> method.
     * 
     * @param input
     *          the <code>InputStream</code> to read from
     * @param output
     *          the <code>OutputStream</code> to write to
     * @return the number of bytes copied, or -1 if &gt; Integer.MAX_VALUE
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.1
     */
    public static int copy(InputStream input, OutputStream output)
            throws IOException {
        long count = copyLarge(input, output);
        if (count > Integer.MAX_VALUE) {
            return -1;
        }
        return (int) count;
    }
    /**
     * Copy bytes from an <code>InputStream</code> to chars on a <code>Writer</code> using the default character encoding of the platform.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
     * <p>
     * This method uses {@link InputStreamReader}.
     * 
     * @param input
     *          the <code>InputStream</code> to read from
     * @param output
     *          the <code>Writer</code> to write to
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.1
     */
    public static void copy(InputStream input, Writer output)
            throws IOException {
        InputStreamReader in = new InputStreamReader(input);
        copy(in, output);
    }
    /**
     * Copy bytes from an <code>InputStream</code> to chars on a <code>Writer</code> using the specified character encoding.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
     * <p>
     * Character encoding names can be found at <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
     * <p>
     * This method uses {@link InputStreamReader}.
     * 
     * @param input
     *          the <code>InputStream</code> to read from
     * @param output
     *          the <code>Writer</code> to write to
     * @param encoding
     *          the encoding to use, null means platform default
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.1
     */
    public static void copy(InputStream input, Writer output,
            String encoding) throws IOException {
        if (encoding == null) {
            copy(input, output);
        } else {
            InputStreamReader in = new InputStreamReader(input, encoding);
            copy(in, output);
        }
    }
    /**
     * Copy chars from a <code>Reader</code> to a <code>Writer</code>.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedReader</code>.
     * <p>
     * Large streams (over 2GB) will return a chars copied value of <code>-1</code> after the copy has completed since the correct number of chars cannot be returned as an int. For large streams use the <code>copyLarge(Reader, Writer)</code> method.
     * 
     * @param input
     *          the <code>Reader</code> to read from
     * @param output
     *          the <code>Writer</code> to write to
     * @return the number of characters copied, or -1 if &gt; Integer.MAX_VALUE
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.1
     */
    public static int copy(Reader input, Writer output) throws IOException {
        long count = copyLarge(input, output);
        if (count > Integer.MAX_VALUE) {
            return -1;
        }
        return (int) count;
    }
    /**
     * Copy chars from a <code>Reader</code> to bytes on an <code>OutputStream</code> using the default character encoding of the platform, and calling flush.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedReader</code>.
     * <p>
     * Due to the implementation of OutputStreamWriter, this method performs a flush.
     * <p>
     * This method uses {@link OutputStreamWriter}.
     * 
     * @param input
     *          the <code>Reader</code> to read from
     * @param output
     *          the <code>OutputStream</code> to write to
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.1
     */
    public static void copy(Reader input, OutputStream output)
            throws IOException {
        OutputStreamWriter out = new OutputStreamWriter(output);
        copy(input, out);
        // XXX Unless anyone is planning on rewriting OutputStreamWriter, we
        // have to flush here.
        out.flush();
    }
    /**
     * Copy chars from a <code>Reader</code> to bytes on an <code>OutputStream</code> using the specified character encoding, and calling flush.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedReader</code>.
     * <p>
     * Character encoding names can be found at <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
     * <p>
     * Due to the implementation of OutputStreamWriter, this method performs a flush.
     * <p>
     * This method uses {@link OutputStreamWriter}.
     * 
     * @param input
     *          the <code>Reader</code> to read from
     * @param output
     *          the <code>OutputStream</code> to write to
     * @param encoding
     *          the encoding to use, null means platform default
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.1
     */
    public static void copy(Reader input, OutputStream output,
            String encoding) throws IOException {
        if (encoding == null) {
            copy(input, output);
        } else {
            OutputStreamWriter out = new OutputStreamWriter(output,
                    encoding);
            copy(input, out);
            // XXX Unless anyone is planning on rewriting OutputStreamWriter,
            // we have to flush here.
            out.flush();
        }
    }
    /**
     * Copy bytes from a large (over 2GB) <code>InputStream</code> to an <code>OutputStream</code>.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
     * 
     * @param input
     *          the <code>InputStream</code> to read from
     * @param output
     *          the <code>OutputStream</code> to write to
     * @return the number of bytes copied
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.3
     */
    public static long copyLarge(InputStream input, OutputStream output)
            throws IOException {
        byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
        long count = 0;
        int n = 0;
        while (-1 != (n = input.read(buffer))) {
            output.write(buffer, 0, n);
            count += n;
        }
        return count;
    }
    /**
     * Copy chars from a large (over 2GB) <code>Reader</code> to a <code>Writer</code>.
     * <p>
     * This method buffers the input internally, so there is no need to use a <code>BufferedReader</code>.
     * 
     * @param input
     *          the <code>Reader</code> to read from
     * @param output
     *          the <code>Writer</code> to write to
     * @return the number of characters copied
     * @throws NullPointerException
     *           if the input or output is null
     * @throws IOException
     *           if an I/O error occurs
     * @since Commons IO 1.3
     */
    public static long copyLarge(Reader input, Writer output)
            throws IOException {
        char[] buffer = new char[DEFAULT_BUFFER_SIZE];
        long count = 0;
        int n = 0;
        while (-1 != (n = input.read(buffer))) {
            output.write(buffer, 0, n);
            count += n;
        }
        return count;
    }
}

Related Tutorials