io.pkts.packet.sip.impl

Class PreConditions

java.lang.Object

io.pkts.packet.sip.impl.PreConditions

public final class PreConditions
extends Object

Contains common checks for null etc. All assertXXXX will throw a SipParseException. All checkXXX will return a boolean and all ensureXXX will throw an IllegalArgumentException. Note that assertXXX and enxureXXX are the exact same thing except that they throw different exception. The only reason for this is that sometimes I want to throw a SipParseException and sometimes I want to throw an IllegalArgumentException.

Author:

jonas@jonasborjesson.com

Method Summary

Modifier and Type	Method and Description
static void	assertArgument(boolean expression, String msg)
static Buffer	assertNotEmpty(Buffer reference, String msg) Assert that the Buffer is not null nor empty.
static String	assertNotEmpty(String reference, String msg)
static <T> T	assertNotNull(T reference)
static <T> T	assertNotNull(T reference, String msg)
static boolean	checkIfEmpty(String string) Check if a string is empty, which includes null check.
static boolean	checkIfNotEmpty(String string)
static void	ensureArgument(boolean expression, String msg)
static Buffer	ensureNotEmpty(Buffer reference, String msg) Assert that the Buffer is not null nor empty.
static String	ensureNotEmpty(String reference, String msg)
static <T> T	ensureNotNull(T reference)
static <T> T	ensureNotNull(T reference, String msg)
static <T> T	ifNull(T reference, T defaultValue) If our reference is null then return a default value instead.

Methods inherited from class java.lang.Object

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

Method Detail

ensureNotNull

public static <T> T ensureNotNull(T reference,
                                  String msg)
                           throws IllegalArgumentException

Throws:

IllegalArgumentException

ensureNotNull

public static <T> T ensureNotNull(T reference)
                           throws IllegalArgumentException

Throws:

IllegalArgumentException

assertNotNull

public static <T> T assertNotNull(T reference,
                                  String msg)
                           throws SipParseException

Throws:

SipParseException

assertNotNull

public static <T> T assertNotNull(T reference)
                           throws SipParseException

Throws:

SipParseException

checkIfEmpty

public static boolean checkIfEmpty(String string)

Check if a string is empty, which includes null check.

Parameters:

string -

Returns:

true if the string is either null or empty

checkIfNotEmpty

public static boolean checkIfNotEmpty(String string)

ensureNotEmpty

public static String ensureNotEmpty(String reference,
                                    String msg)
                             throws IllegalArgumentException

Throws:

IllegalArgumentException

ensureArgument

public static void ensureArgument(boolean expression,
                                  String msg)
                           throws IllegalArgumentException

Throws:

IllegalArgumentException

assertNotEmpty

public static String assertNotEmpty(String reference,
                                    String msg)
                             throws SipParseException

Throws:

SipParseException

assertArgument

public static void assertArgument(boolean expression,
                                  String msg)
                           throws SipParseException

Throws:

SipParseException

assertNotEmpty

public static Buffer assertNotEmpty(Buffer reference,
                                    String msg)
                             throws SipParseException

Assert that the Buffer is not null nor empty.

Parameters:

reference -

msg -

Returns:

Throws:

IllegalArgumentException

SipParseException

ensureNotEmpty

public static Buffer ensureNotEmpty(Buffer reference,
                                    String msg)
                             throws IllegalArgumentException

Assert that the Buffer is not null nor empty.

Parameters:

reference -

msg -

Returns:

Throws:

IllegalArgumentException

ifNull

public static <T> T ifNull(T reference,
                           T defaultValue)

If our reference is null then return a default value instead.

Parameters:

reference - the thing to check.

defaultValue - the default value to return if the above reference is null.

Returns:

the reference if not null, otherwise the default value. Note, if your default value is null as well then you will get back null, since that is what you asked. Chain with assertNotNull(Object, String) if you want to make sure you have a non-null value for the default value.