Java InputStreamReader Read readFile(File file, String encoding)

Description

read File

License

Apache License

Declaration

public static String readFile(File file, String encoding) throws IOException 

Method Source Code

//package com.java2s;
//License from project: Apache License 

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;

import java.io.ByteArrayInputStream;

import java.io.File;
import java.io.FileInputStream;

import java.io.FileOutputStream;
import java.io.FileReader;
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.UnsupportedEncodingException;
import java.io.Writer;

public class Main {
    public static final int BUFFER_SIZE = 4096;

    public static String readFile(File file) throws IOException {
        Reader in = new FileReader(file);
        StringWriter out = new StringWriter();
        copy(in, out);/* ww w. jav  a 2 s . c o m*/
        return out.toString();
    }

    public static String readFile(File file, String encoding) throws IOException {
        InputStream inputStream = new FileInputStream(file);
        return toString(encoding, inputStream);
    }

    /**
     * Copy the contents of the given input File to the given output File.
     * 
     * @param in the file to copy from
     * @param out the file to copy to
     * @return the number of bytes copied
     * @throws java.io.IOException in case of I/O errors
     */
    public static int copy(File in, File out) throws IOException {
        return copy(new BufferedInputStream(new FileInputStream(in)),
                new BufferedOutputStream(new FileOutputStream(out)));
    }

    /**
     * Copy the contents of the given byte array to the given output File.
     * 
     * @param in the byte array to copy from
     * @param out the file to copy to
     * @throws IOException in case of I/O errors
     */
    public static void copy(byte[] in, File out) throws IOException {
        ByteArrayInputStream inStream = new ByteArrayInputStream(in);
        OutputStream outStream = new BufferedOutputStream(new FileOutputStream(out));
        copy(inStream, outStream);
    }

    /**
     * Copy the contents of the given InputStream to the given OutputStream. Closes both streams when done.
     * 
     * @param in the stream to copy from
     * @param out the stream to copy to
     * @return the number of bytes copied
     * @throws IOException in case of I/O errors
     */
    public static int copy(InputStream in, OutputStream out) throws IOException {
        try {
            int byteCount = 0;
            byte[] buffer = new byte[BUFFER_SIZE];
            int bytesRead = -1;
            while ((bytesRead = in.read(buffer)) != -1) {
                out.write(buffer, 0, bytesRead);
                byteCount += bytesRead;
            }
            out.flush();
            return byteCount;
        } finally {
            try {
                in.close();
            } catch (IOException ex) {
            }
            try {
                out.close();
            } catch (IOException ex) {
            }
        }
    }

    /**
     * Copy the contents of the given byte array to the given OutputStream. Closes the stream when done.
     * 
     * @param in the byte array to copy from
     * @param out the OutputStream to copy to
     * @throws IOException in case of I/O errors
     */
    public static void copy(byte[] in, OutputStream out) throws IOException {
        try {
            out.write(in);
        } finally {
            try {
                out.close();
            } catch (IOException ex) {
            }
        }
    }

    /**
     * Copy the contents of the given Reader to the given Writer. Closes both when done.
     * 
     * @param in the Reader to copy from
     * @param out the Writer to copy to
     * @return the number of characters copied
     * @throws IOException in case of I/O errors
     */
    public static int copy(Reader in, Writer out) throws IOException {
        try {
            int byteCount = 0;
            char[] buffer = new char[BUFFER_SIZE];
            int bytesRead = -1;
            while ((bytesRead = in.read(buffer)) != -1) {
                out.write(buffer, 0, bytesRead);
                byteCount += bytesRead;
            }
            out.flush();
            return byteCount;
        } finally {
            try {
                in.close();
            } catch (IOException ex) {
            }
            try {
                out.close();
            } catch (IOException ex) {
            }
        }
    }

    /**
     * Copy the contents of the given String to the given output Writer. Closes the write when done.
     * 
     * @param in the String to copy from
     * @param out the Writer to copy to
     * @throws IOException in case of I/O errors
     */
    public static void copy(String in, Writer out) throws IOException {
        try {
            out.write(in);
        } finally {
            try {
                out.close();
            } catch (IOException ex) {
            }
        }
    }

    public static String toString(InputStream inputStream) throws UnsupportedEncodingException, IOException {
        Reader reader = new InputStreamReader(inputStream);
        StringWriter writer = new StringWriter();
        copy(reader, writer);
        return writer.toString();
    }

    public static String toString(String encoding, InputStream inputStream)
            throws UnsupportedEncodingException, IOException {
        Reader reader = new InputStreamReader(inputStream, encoding);
        StringWriter writer = new StringWriter();
        copy(reader, writer);
        return writer.toString();
    }
}

Related

1. readFile(File file)
2. readFile(File file, String default_encoding)
3. readFile(File file, String encoding)
4. readFile(File file, String encoding)
5. readFile(File file, String encoding)
6. readFile(File filename)
7. readFile(File path)
8. readFile(File resultFile)
9. readFile(File target)