de.fhg.igd.gps
Class NMEA183Sentence

java.lang.Object
  de.fhg.igd.gps.NMEA183Sentence

Direct Known Subclasses:

NMEA183GGASentence, NMEA183GLLSentence, NMEA183GSASentence, NMEA183GSVSentence, NMEA183RMCSentence, NMEA183VTGSentence

public class NMEA183Sentence

extends Object

This class represents a generic NMEA183 sentence.

Author:

Dennis Bartussek

Field Summary

protected byte	checksum_ The checksum of this sentence.
protected List	fields_
protected String	sentenceId_
protected String	sentenceId_desc_
protected String	talkerId_
protected String	talkerId_desc_

Constructor Summary

NMEA183Sentence()
Constructs a new NMEA183Sentence.

NMEA183Sentence(String talkerId)
Constructs a new NMEA183Sentence with the specified talkerId.

NMEA183Sentence(String talkerId, String sentenceId)
Constructs a new NMEA183Sentence with the specified talkerId and sentenceId.

Method Summary

protected String	bodyToString() Returns the body part of this sentence's string representation.
protected byte	computeChecksum() Computes the checksum that is valid for this NMEA183Sentence.
protected Date	getDateField(int index) Returns the element of fields_ at the specified index, transformed into a Date object.
protected double	getFloatField(int index) Returns the element of fields_ at the specified index, transformed into a double value.
protected int	getIntegerField(int index) Returns the element of fields_ at the specified index, transformed into an int value.
protected Latitude	getLatitudeField(int index) Returns the element of fields_ at the specified index, transformed into a Latitude object.
protected Longitude	getLongitudeField(int index) Returns the element of fields_ at the specified index, transformed into a Longitude object.
String	getSentenceId() Returns the sentence id of this NMEA183Sentence.
protected String	getStringField(int index) Returns the element of fields_ at the specified index as a String object.
boolean	hasChecksum() Tests whether a checksum has been specified for this NMEA183Sentence or not.
protected String	headerToString() Returns the header part of this sentence's string representation, which consists of: the talker id the sentence id the checksum
private String	lookupTalkerId(String id) Returns the description of the specified talker id.
void	parse(NMEA183Tokenizer tokenizer) Reads and parses a NMEA183 sentence from tokenizer.
protected byte[]	rebuildSentence() Builds a nmea sentence string based on fields_.
String	toString() Returns the string representation of this NMEA183Sentence.
boolean	valid() Tests whether the specified checksum is valid for this NMEA183Sentence or not.

Methods inherited from class java.lang.Object

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

Field Detail

sentenceId_desc_

protected String sentenceId_desc_

talkerId_desc_

protected String talkerId_desc_

sentenceId_

protected String sentenceId_

talkerId_

protected String talkerId_

fields_

protected List fields_

checksum_

protected byte checksum_

The checksum of this sentence. A value of 0 indicates that a checksum has not been specified for this sentence.

Constructor Detail

NMEA183Sentence

public NMEA183Sentence()

Constructs a new NMEA183Sentence.

NMEA183Sentence

public NMEA183Sentence(String talkerId)

Constructs a new NMEA183Sentence with the specified talkerId.

Parameters:

talkerId - the talker id of this NMEA183Sentence

NMEA183Sentence

public NMEA183Sentence(String talkerId,
                       String sentenceId)

Constructs a new NMEA183Sentence with the specified talkerId and sentenceId.

Parameters:

talkerId - the talker id of this NMEA183Sentence

sentenceId - the sentence id of this NMEA183Sentence

Method Detail

hasChecksum

public boolean hasChecksum()

Tests whether a checksum has been specified for this NMEA183Sentence or not.

Returns:

true if a checksum has been specified; otherwise false

valid

public boolean valid()

Tests whether the specified checksum is valid for this NMEA183Sentence or not.

Returns:

true if checksum is valid for this sentence or if checksum has not been specified, false if checksum is invalid for this NMEA183Sentence.

parse

public void parse(NMEA183Tokenizer tokenizer)
           throws NMEA183SentenceFormatException

Reads and parses a NMEA183 sentence from tokenizer.

Parameters:

tokenizer - the NMEA183Tokenizer to read from

Throws:

NMEA183SentenceFormatException - if the read sentence does not have the appropriate format

getSentenceId

public String getSentenceId()

Returns the sentence id of this NMEA183Sentence.

Returns:

the sentence id of this NMEA183Sentence.

toString

public String toString()

Returns the string representation of this NMEA183Sentence.

Returns:

the string representation of this NMEA183Sentence.

lookupTalkerId

private String lookupTalkerId(String id)

Returns the description of the specified talker id. If id is not known the String "unknown" is returned.

Parameters:

id - the talker id to query

Returns:

the description of the specified talker id.

getDateField

protected Date getDateField(int index)
                     throws IndexOutOfBoundsException

Returns the element of fields_ at the specified index, transformed into a Date object. The index argument is expected to be more than 0 and less than fields_.size().

Parameters:

index - the index of the element to get

Throws:

IndexOutOfBoundsException - if index is less than 0 or more than fields_.size()

getFloatField

protected double getFloatField(int index)
                        throws IndexOutOfBoundsException,
                               NumberFormatException

Returns the element of fields_ at the specified index, transformed into a double value. The index argument is expected to be more than 0 and less than fields_.size().

Parameters:

index - the index of the element to get

Throws:

IndexOutOfBoundsException - if index is less than 0 or more than fields_.size()

NumberFormatException - if the element at the given index does not have the appropriate format

getIntegerField

protected int getIntegerField(int index)
                       throws IndexOutOfBoundsException,
                              NumberFormatException

Returns the element of fields_ at the specified index, transformed into an int value. The index argument is expected to be more than 0 and less than fields_.size().

Parameters:

index - the index of the element to get

Throws:

IndexOutOfBoundsException - if index is less than 0 or more than fields_.size()

NumberFormatException - if the element at the given index does not have the appropriate format

getLatitudeField

protected Latitude getLatitudeField(int index)
                             throws IndexOutOfBoundsException,
                                    AngularDistanceFormatException

Returns the element of fields_ at the specified index, transformed into a Latitude object. The index argument is expected to be more than 0 and less than fields_.size() - 1.

Note: This method actually reads 2 elements, at index and index+1

Parameters:

index - the starting index of the elements to get

Throws:

IndexOutOfBoundsException - if index is less than 0 or more than fields_.size() - 1

AngularDistanceFormatException - if the element at the given index does not have the appropriate format

getLongitudeField

protected Longitude getLongitudeField(int index)
                               throws IndexOutOfBoundsException,
                                      AngularDistanceFormatException

Returns the element of fields_ at the specified index, transformed into a Longitude object. The index argument is expected to be more than 0 and less than fields_.size() - 1.

Note: This method actually reads 2 elements, at index and index+1

Parameters:

index - the starting index of the elements to get

Throws:

IndexOutOfBoundsException - if index is less than 0 or more than fields_.size() - 1

AngularDistanceFormatException - if the element at the given index does not have the appropriate format

getStringField

protected String getStringField(int index)
                         throws IndexOutOfBoundsException

Returns the element of fields_ at the specified index as a String object. The index argument is expected to be more than 0 and less than fields_.size().

Parameters:

index - the index of the element to get

Throws:

IndexOutOfBoundsException - if index is less than 0 or more than fields_.size()

bodyToString

protected String bodyToString()

Returns the body part of this sentence's string representation.

Returns:

the body part of this sentence's string representation.

See Also:

toString()

headerToString

protected String headerToString()

Returns the header part of this sentence's string representation, which consists of:

• the talker id
• the sentence id
• the checksum

Returns:

the header part of this sentence's string representation

See Also:

toString()

rebuildSentence

protected byte[] rebuildSentence()

Builds a nmea sentence string based on fields_.

Returns:

the rebuild nmea sentence

computeChecksum

protected byte computeChecksum()

Computes the checksum that is valid for this NMEA183Sentence. The calculation is based on the rebuild sentence returned by the rebuildSentence method.

Returns:

the checksum that is valid for this NMEA183Sentence