Package org.opennms.netmgt.poller.monitors.support

Class DNSInputStream

java.lang.Object

java.io.InputStream

java.io.ByteArrayInputStream

org.opennms.netmgt.poller.monitors.support.DNSInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class DNSInputStream
extends ByteArrayInputStream

DNSInputStrean extends a ByteArrayInputStream and has methods to decode the data of a DNS response to an address resquest.

Version:

$Id: $

Author:

Sowmya , OpenNMS , Sowmya , OpenNMS

Field Summary

Fields inherited from class java.io.ByteArrayInputStream

buf, count, mark, pos

Constructor Summary

Constructors

Constructor	Description
DNSInputStream(byte[] data)	Constructs a new input stream for decoding DNS records.
DNSInputStream(byte[] data, int off, int len)	Constructs a DNSInputStream object from the byte array.

Method Summary

Modifier and Type	Method	Description
int	readByte()	Read a byte off the input stream.
String	readDomainName()	The readDomainName method is used to read an entire domain name from the stream.
long	readInt()	Read an 'int' off the input stream.
DNSAddressRR	readRR()	Reads the resource record from the input stream.
int	readShort()	Read a 'short' off the input stream.
String	readString()	Read a 'string' off the input stream.

Methods inherited from class java.io.ByteArrayInputStream

available, close, mark, markSupported, read, read, readAllBytes, readNBytes, reset, skip, transferTo

Methods inherited from class java.io.InputStream

nullInputStream, read, readNBytes

Methods inherited from class java.lang.Object

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

Constructor Detail

DNSInputStream

public DNSInputStream(byte[] data)

Constructs a new input stream for decoding DNS records.

Parameters:

data - The array of data to pass to the base class.

DNSInputStream

public DNSInputStream(byte[] data,
                      int off,
                      int len)

Constructs a DNSInputStream object from the byte array.

Parameters:

data - byte array containing the response data

off - offset of the data in the byte array

len - length of the byte array

Method Detail

readByte

public int readByte()
             throws IOException

Read a byte off the input stream.

Returns:

The integer read.

Throws:

IOException - Thrown if the end-of-file is encountered trying to read the next byte.

IOException - if any.

readShort

public int readShort()
              throws IOException

Read a 'short' off the input stream.

Returns:

The short from the input stream.

Throws:

IOException - Thrown if the end-of-file is encountered trying to read the next short.

IOException - if any.

readInt

public long readInt()
             throws IOException

Read an 'int' off the input stream.

Returns:

The int from the input stream.

Throws:

IOException - Thrown if there is an error while read.

IOException - if any.

readString

public String readString()
                  throws IOException

Read a 'string' off the input stream.

Returns:

the string from the input stream

Throws:

IOException - Thrown if there is an error while read

IOException - if any.

readDomainName

public String readDomainName()
                      throws IOException

The readDomainName method is used to read an entire domain name from the stream. The string returned will be the concatentation of several substrings, each substring in the record is separated by a '.'(dot). For more information see the RFC for the distributed name service.

Returns:

The domain name string.

Throws:

IOException - Thrown if an error occurs decoding the string from the stream.

IOException - if any.

readRR

public DNSAddressRR readRR()
                    throws IOException

Reads the resource record from the input stream.

Returns:

The DNSAddressRR that is in response to the address request.

Throws:

IOException - Thrown if data does not decode to a DNSAddressRRl.

IOException - if any.