com.google.enterprise.adaptor

Class IOHelper

java.lang.Object

com.google.enterprise.adaptor.IOHelper

public class IOHelper
extends Object

Utility class for providing useful methods when handling streams or other forms of I/O.

Method Summary

Modifier and Type	Method and Description
static void	copyStream(InputStream in, OutputStream out) Copy contents of in to out.
static int	readFully(InputStream is, byte[] bytes, int off, int len) Reads a specified number of bytes from a stream.
static byte[]	readInputStreamToByteArray(InputStream instream) Read the contents of is into a byte array.
static String	readInputStreamToString(InputStream instream, Charset charset) Form a string from the contents of instream with charset charset.
static File	writeToTempFile(InputStream in) Write contents of in to a temporary file.
static File	writeToTempFile(String string, Charset charset) Write contents of string to a temporary file, encoded using charset.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

copyStream

public static void copyStream(InputStream in,
                              OutputStream out)
                       throws IOException

Copy contents of in to out.

Parameters:

in - is source of bytes

out - is destination for bytes

Throws:

IOException - if reading or writing fails

readInputStreamToByteArray

public static byte[] readInputStreamToByteArray(InputStream instream)
                                         throws IOException

Read the contents of is into a byte array.

Parameters:

instream - to be read

Returns:

byte[] entire instream bytes

Throws:

IOException - when reading fails

readInputStreamToString

public static String readInputStreamToString(InputStream instream,
                                             Charset charset)
                                      throws IOException

Form a string from the contents of instream with charset charset.

Parameters:

instream - to be read

charset - is encoding of input stream's bytes

Returns:

String entire instream contents

Throws:

IOException - when reading fails

writeToTempFile

public static File writeToTempFile(InputStream in)
                            throws IOException

Write contents of in to a temporary file. Caller is responsible for deleting the temporary file after use.

Parameters:

in - written into file

Returns:

File handle for written file

Throws:

IOException - when writing file fails

writeToTempFile

public static File writeToTempFile(String string,
                                   Charset charset)
                            throws IOException

Write contents of string to a temporary file, encoded using charset. Caller is responsible for deleting the temporary file after use.

Parameters:

string - written into file

charset - is encoding of written file

Returns:

File handle for written file

Throws:

IOException - when writing file fails

readFully

public static int readFully(InputStream is,
                            byte[] bytes,
                            int off,
                            int len)
                     throws IOException

Reads a specified number of bytes from a stream. Fewer bytes will only be returned if the end of stream has been reached.

Parameters:

is - the stream from which the bytes will be read.

bytes - the buffer into which the data is read.

off - the start offset in array b at which the data is written.

len - the number of bytes to read unless end of stream is encountered

Returns:

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Throws:

IOException - If the first byte cannot be read for any reason other than reaching end-of-stream, or if the input stream has been closed, or if some other I/O error occurs.

NullPointerException - If b is null.

IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off