OSMQ
v2.0.1

osmq.io
Class StringInputStream

java.lang.Object
  extended byjava.io.InputStream
      extended byjava.io.FilterInputStream
          extended byosmq.io.StringInputStream
All Implemented Interfaces:
ReaderStream

public class StringInputStream
extends java.io.FilterInputStream
implements ReaderStream

An input stream filer that supports reading an input stream as newline-delimited strings.

Note this class assumes a single reader and is NOT thread safe.


Constructor Summary
StringInputStream(java.io.InputStream in)
           
 
Method Summary
 int read(byte[] b, int off, int len)
          Reads len bytes of data from the input stream into an array of bytes.
 byte[] readBytes()
           
 int readBytes(byte[] target)
           
 java.lang.String readln()
           
 
Methods inherited from class java.io.FilterInputStream
available, close, mark, markSupported, read, read, reset, skip
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface osmq.io.ReaderStream
close
 

Constructor Detail

StringInputStream

public StringInputStream(java.io.InputStream in)
Method Detail

readBytes

public int readBytes(byte[] target)
              throws java.io.IOException
Specified by:
readBytes in interface ReaderStream
Throws:
java.io.IOException

readBytes

public byte[] readBytes()
                 throws java.io.IOException
Specified by:
readBytes in interface ReaderStream
Throws:
java.io.IOException

readln

public java.lang.String readln()
                        throws java.io.IOException
Specified by:
readln in interface ReaderStream
Throws:
java.io.IOException

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException
Reads len bytes of data from the input stream into an array of bytes. The number of bytes actually read is returned as an integer.

NOTE This method blocks until input len is available, end of file is detected, or an exception is thrown. This is different from the normal InputStream contract that may return less than len

If b is null, a NullPointerException is thrown.

If off is negative, or len is negative, or off+len is greater than the length of the array b, then an IndexOutOfBoundsException is thrown.

If len is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at end of file, the value -1 is returned; otherwise, at least one byte is read and stored into b.

The first byte read is stored into element b[off], the next one into b[off+1], and so on. The number of bytes read is, at most, equal to len. Let k be the number of bytes actually read; these bytes will be stored in elements b[off] through b[off+k-1], leaving elements b[off+k] through b[off+len-1] unaffected.

In every case, elements b[0] through b[off] and elements b[off+len] through b[b.length-1] are unaffected.

If the first byte cannot be read for any reason other than end of file, then an IOException is thrown. In particular, an IOException is thrown if the input stream has been closed.

The read(b, off, len) method for class InputStream simply calls the method read() repeatedly. If the first such call results in an IOException, that exception is returned from the call to the read(b, off, len) method. If any subsequent call to read() results in a IOException, the exception is caught and treated as if it were end of file; the bytes read up to that point are stored into b and the number of bytes read before the exception occurred is returned. Subclasses are encouraged to provide a more efficient implementation of this method.

Parameters:
b - the buffer into which the data is read.
off - the start offset in array b at which the data is written.
len - the maximum number of bytes to read.
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:
java.io.IOException - if an I/O error occurs.
See Also:
InputStream.read(byte[], int, int)

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All Rights Reserved