AX25Callsign

java.lang.Object
- org.ka2ddo.ax25.AX25Callsign

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Comparable<AX25Callsign>
```
public final class AX25Callsign
extends java.lang.Object
implements java.lang.Comparable<AX25Callsign>, java.lang.Cloneable, java.io.Serializable
```
This class defines a single AX.25 callsign (address).

Author:

Andrew Pavlin, KA2DDO

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`static java.util.Comparator<AX25Callsign>`	`CALLSIGN_COMPARATOR` A Comparator to use for callsigns when it is more efficient than using the Comparable interface to AX25Callsign.
`boolean`	`h_c` Has_been_repeated flag (for digipeater callsigns) or command/response flags (for destination and source callsigns).
`boolean`	`last` Flag bit in SSID byte indicating this is the last callsign in a digipeater sequence.
`boolean`	`valid` Indicates whether the callsign in this object can be exported as a valid AX.25 binary protocol address.

Constructor Summary

Constructors
Constructor and Description
`AX25Callsign()` Construct an empty but assumed-valid callsign.
`AX25Callsign(byte[] buf, int offset, int length)` Extract an AX.25 callsign from an AX.25 frame byte array in network byte order.
`AX25Callsign(int startPos, int endPos, byte[] byteCallsign)` Construct a AX25Callsign from the specified part of the byte array of text containing the callsign.
`AX25Callsign(java.lang.String textCallsign)` Construct a AX25Callsign from the string representation of the callsign.
`AX25Callsign(java.lang.String textCallsign, int startPos, int endPos)` Construct a AX25Callsign from the specified sub-string representation of the callsign.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`java.lang.Object`	`clone()` Creates and returns a copy of this object.
`int`	`compareTo(AX25Callsign o)` Compares this object with the specified object for order.
`void`	`decrementSSID()` Decrement a non-zero SSID value, as is done for NewN-n paradigm digipeat aliases.
`AX25Callsign`	`dup()` Create a shallow clone of this AX25Callsign, discarding any cached toString() value.
`boolean`	`equals(java.lang.Object o)` Test if some other object is the same as this AX25Callsign.
`java.lang.String`	`getBaseCallsign()` Gets the base callsign (without the AX.25 SSID extension).
`static byte`	`getDefaultReserved()` Get the current default value for the reserved bits of the AX25 callsign SSID byte.
`byte`	`getReserved()` Get the reserved bits of the 7th byte of the callsign (per the AX.25 specification).
`int`	`getSSID()` Return the numeric SSID associated with this callsign.
`boolean`	`hasBeenRepeated()` Report if the hasBeenRepeated flag in the callsign is set.
`int`	`hashCode()` Returns a hash code for this callsign.
`static boolean`	`isDigipeatableCallsign(java.lang.String callsign)` Test if a callsign looks like a real callsign (at least one digit somewhere other than the last character, all letters uppercase), and an AX.25-legal SSID.
`boolean`	`isNewNParadigmAlias()` Test if this callsign appears to be a valid New n-N digipeat alias.
`static boolean`	`isNewNParadigmAlias(java.lang.String callsign)` Test if the parameter appears to be a valid New n-N digipeat alias.
`static boolean`	`isOldParadigmAlias(java.lang.String callsign)` Test if the parameter appears to be an old paradigm digipeat alias.
`static boolean`	`isRealCallsign(java.lang.String callsign)` Test if a callsign looks like a real callsign (at least one digit somewhere other than the last character, all letters uppercase).
`boolean`	`isValid()` Indicates if this callsign has valid syntax to be transmitted in the header of an AX.25 frame.
`static void`	`setDefaultReserved(byte defaultReserved)` Set the default value for the reserved bits of newly generated AX25 callsign SSID byte.
`void`	`setReserved(byte reserved)` Set the reserved bits of the 7th byte of the callsign (per the AX.25 specification).
`void`	`setSSID(int ssid)` Specify the numeric SSID associated with this callsign.
`java.lang.String`	`toAnnotatedString()` Return a String representing this AX25Frame object, with an additional note if the reserved field in the SSID byte is not the default value.
`byte[]`	`toByteArray()` Return the callsign as the actual byte sequence that would be transmitted over the air (without HDLC bit-stuffing).
`java.lang.String`	`toString()` Return a String representing this AX25Callsign object.
`void`	`write(java.io.OutputStream os, boolean last)` Encode this AX25Callsign into binary radio transmission format on a stream.

Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - h_c
```
public boolean h_c
```
    Has_been_repeated flag (for digipeater callsigns) or command/response flags (for destination and source callsigns).
  - last
```
public boolean last
```
    Flag bit in SSID byte indicating this is the last callsign in a digipeater sequence.
  - valid
```
public boolean valid
```
    Indicates whether the callsign in this object can be exported as a valid AX.25 binary protocol address.
  - CALLSIGN_COMPARATOR
```
public static final java.util.Comparator<AX25Callsign> CALLSIGN_COMPARATOR
```
    A Comparator to use for callsigns when it is more efficient than using the Comparable interface to AX25Callsign.
    
    See Also:
    
    compareTo(AX25Callsign)
- Constructor Detail
  - AX25Callsign
```
public AX25Callsign()
```
    Construct an empty but assumed-valid callsign.
  - AX25Callsign
```
public AX25Callsign(java.lang.String textCallsign)
```
    Construct a AX25Callsign from the string representation of the callsign.
    
    Parameters:
    
    textCallsign - String to parse into an AX.25-compliant callsign
  - AX25Callsign
```
public AX25Callsign(java.lang.String textCallsign,
                    int startPos,
                    int endPos)
```
    Construct a AX25Callsign from the specified sub-string representation of the callsign.
    
    Parameters:
    
    textCallsign - String to parse into an AX.25-compliant callsign
    
    startPos - int position in string where callsign starts
    
    endPos - int position in string where callsign ends
  - AX25Callsign
```
public AX25Callsign(int startPos,
                    int endPos,
                    byte[] byteCallsign)
```
    Construct a AX25Callsign from the specified part of the byte array of text containing the callsign.
    
    Parameters:
    
    startPos - int position in byte array where callsign starts
    
    endPos - int position in byte array where callsign ends
    
    byteCallsign - byte array of ASCII text to parse into an AX.25-compliant callsign
  - AX25Callsign
```
public AX25Callsign(byte[] buf,
                    int offset,
                    int length)
             throws java.lang.IndexOutOfBoundsException,
                    java.lang.IllegalArgumentException
```
    Extract an AX.25 callsign from an AX.25 frame byte array in network byte order. This variant properly handles all the control bits and the fact that the ASCII characters are shifted left one bit according to the AX.25 protocol specification.
    
    Parameters:
    
    buf - byte array containing the AX.25-encoded callsign
    
    offset - index into the array where the callsign begins
    
    length - bytes remaining in the array after the offset
    
    Throws:
    
    java.lang.IndexOutOfBoundsException - if not enough bytes left in the array to contain an AX.25 callsign
    
    java.lang.IllegalArgumentException - if the callsign has an invalid format, such as embedded whitespace in the middle of a callsign with following non-blank characters
- Method Detail
  - isRealCallsign
```
public static boolean isRealCallsign(java.lang.String callsign)
```
    Test if a callsign looks like a real callsign (at least one digit somewhere other than the last character, all letters uppercase). Note this will automatically strip off the SSID (if any) before testing. Note this is safe for empty strings, and will properly report them as not being a valid real-station callsign,
    
    Parameters:
    
    callsign - String callsign to test
    
    Returns:
    
    boolean true if callsign looks like real
  - isDigipeatableCallsign
```
public static boolean isDigipeatableCallsign(java.lang.String callsign)
```
    Test if a callsign looks like a real callsign (at least one digit somewhere other than the last character, all letters uppercase), and an AX.25-legal SSID. Note this is safe for empty strings, and will properly report them as not being a valid real-station callsign,
    
    Parameters:
    
    callsign - String callsign to test
    
    Returns:
    
    boolean true if callsign looks like real
  - isNewNParadigmAlias
```
public boolean isNewNParadigmAlias()
```
    Test if this callsign appears to be a valid New n-N digipeat alias. Such callsigns are all uppercase ASCII letters except for the last character, which must be a digit between 1 and 7, and the SSID must be less than or equal to the number corresponding to that digit (i.e., WIDE1-7 is not valid).
    
    Returns:
    
    boolean true if this callsign looks like a New n-N digipeat alias
  - isNewNParadigmAlias
```
public static boolean isNewNParadigmAlias(java.lang.String callsign)
```
    Test if the parameter appears to be a valid New n-N digipeat alias. Such callsigns are all uppercase ASCII letters except for the last character, which must be a digit between 1 and 7, and the SSID (if present) must be less than or equal to the number corresponding to that digit (i.e., WIDE1-7 is not valid).
    
    Parameters:
    
    callsign - String supposedly containing an AX.25 callsign
    
    Returns:
    
    boolean true if this callsign looks like a New n-N digipeat alias
  - isOldParadigmAlias
```
public static boolean isOldParadigmAlias(java.lang.String callsign)
```
    Test if the parameter appears to be an old paradigm digipeat alias. Such callsigns are all uppercase ASCII letters.
    
    Parameters:
    
    callsign - String supposedly containing an AX.25 callsign
    
    Returns:
    
    boolean true if this callsign looks like an old digipeat alias
  - equals
```
public boolean equals(java.lang.Object o)
```
    Test if some other object is the same as this AX25Callsign.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    
    o - Object to compare against this callsign
    
    Returns:
    
    boolean true if o is a AX25Callsign with the same value
  - hashCode
```
public int hashCode()
```
    Returns a hash code for this callsign.
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    
    a hash code value for this object.
  - toString
```
public java.lang.String toString()
```
    Return a String representing this AX25Callsign object.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    descriptive String
  - toAnnotatedString
```
public java.lang.String toAnnotatedString()
```
    Return a String representing this AX25Frame object, with an additional note if the reserved field in the SSID byte is not the default value.
    
    Returns:
    
    descriptive String
  - compareTo
```
public int compareTo(AX25Callsign o)
```
    Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. Callsigns are compared in the ASCII order of their strings, then using their SSIDs as a tie-breaker. Note that lowercase is not supposed to be used in a callsign, but this comparator ignores it.
    
    Specified by:
    
    compareTo in interface java.lang.Comparable<AX25Callsign>
    
    Parameters:
    
    o - the object to be compared.
    
    Returns:
    
    a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.
    
    Throws:
    
    java.lang.ClassCastException - if the specified object's type prevents it from being compared to this object.
  - write
```
public void write(java.io.OutputStream os,
                  boolean last)
           throws java.io.IOException
```
    Encode this AX25Callsign into binary radio transmission format on a stream.
    
    Parameters:
    
    os - the OutputStream to write the binary encoding to
    
    last - boolean true if this callsign should have the last bit set in its last byte to indicate there will be no following callsigns according to the AX.25 protocol specification
    
    Throws:
    
    java.io.IOException - if callsign could not be written to the stream
  - toByteArray
```
public byte[] toByteArray()
```
    Return the callsign as the actual byte sequence that would be transmitted over the air (without HDLC bit-stuffing).
    
    Returns:
    
    byte array of the callsign
  - clone
```
public java.lang.Object clone()
```
    Creates and returns a copy of this object.
    
    Overrides:
    
    clone in class java.lang.Object
    
    Returns:
    
    a clone of this instance.
  - dup
```
public AX25Callsign dup()
```
    Create a shallow clone of this AX25Callsign, discarding any cached toString() value.
    
    Returns:
    
    a copy AX25Callsign
  - getBaseCallsign
```
public java.lang.String getBaseCallsign()
```
    Gets the base callsign (without the AX.25 SSID extension). Note that the extension may be included in this string if the overall callsign does not comply with AX.25 requirements.
    
    Returns:
    
    String of the base callsign name
  - getSSID
```
public int getSSID()
```
    Return the numeric SSID associated with this callsign. Will be zero if the overall callsign does not comply with AX.25 requirements.
    
    Returns:
    
    numeric SSID in the range 0 to 15
  - setSSID
```
public void setSSID(int ssid)
```
    Specify the numeric SSID associated with this callsign.
    
    Parameters:
    
    ssid - numeric SSID in the range 0 to 15
  - decrementSSID
```
public void decrementSSID()
```
    Decrement a non-zero SSID value, as is done for NewN-n paradigm digipeat aliases.
  - hasBeenRepeated
```
public boolean hasBeenRepeated()
```
    Report if the hasBeenRepeated flag in the callsign is set.
    
    Returns:
    
    boolean true if the hasBeenRepeated bit is set
  - getReserved
```
public byte getReserved()
```
    Get the reserved bits of the 7th byte of the callsign (per the AX.25 specification).
    
    Returns:
    
    the value of the reserved bits
  - setReserved
```
public void setReserved(byte reserved)
```
    Set the reserved bits of the 7th byte of the callsign (per the AX.25 specification).
    
    Parameters:
    
    reserved - the new value of the reserved bits (masked to the range 0 to 3)
  - isValid
```
public boolean isValid()
```
    Indicates if this callsign has valid syntax to be transmitted in the header of an AX.25 frame.
    
    Returns:
    
    boolean true if callsign is legal for AX.25 frame transmission
  - getDefaultReserved
```
public static byte getDefaultReserved()
```
    Get the current default value for the reserved bits of the AX25 callsign SSID byte.
    
    Returns:
    
    current default RR bit value
  - setDefaultReserved
```
public static void setDefaultReserved(byte defaultReserved)
```
    Set the default value for the reserved bits of newly generated AX25 callsign SSID byte.
    
    Parameters:
    
    defaultReserved - current default RR bit value

Class AX25Callsign

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

h_c

last

valid

CALLSIGN_COMPARATOR

Constructor Detail

AX25Callsign

AX25Callsign

AX25Callsign

AX25Callsign

AX25Callsign

Method Detail

isRealCallsign

isDigipeatableCallsign

isNewNParadigmAlias

isNewNParadigmAlias

isOldParadigmAlias

equals

hashCode

toString

toAnnotatedString

compareTo

write

toByteArray

clone

dup

getBaseCallsign

getSSID

setSSID

decrementSSID

hasBeenRepeated

getReserved

setReserved

isValid

getDefaultReserved

setDefaultReserved