String Predicates

The following additional methods (over ReferenceField) are available to a StringField. The "Condition" in the table below is the condition for which the corresponding Predicate will hold true:

Method Param Type Operation Condition

Method	Param Type	Operation	Condition
isEmpty	`String`	String::isEmpty	the field is empty (i.e. field.length() == 0)
isNotEmpty	`String`	!String::isEmpty	the field is not empty (i.e. field.length() !=0)
equalIgnoreCase	`String`	String::equalsIgnoreCase	the field is equal to the given parameter ignoring case
notEqualIgnoreCase	`String`	!String::equalsIgnoreCase	the field is not equal to the given parameter ignoring case
startsWith	`String`	String::startsWith	the field starts with the given parameter
notStartsWith	`String`	!String::startsWith	the field does not start with the given parameter
startsWithIgnoreCase	`String`	String::startsWith ic	the field starts with the given parameter ignoring case
notStartsWithIgnoreCase	`String`	!String::startsWith ic	the field does not start with the given parameter ignoring case
	endsWith	`String`	String::endsWith
the field ends with the given parameter	notEndsWith	`String`	!String::endsWith
the field does not end with the given parameter	endsWithIgnoreCase	`String`	String::endsWith ic
the field ends with the given parameter	notEndsWithIgnoreCase	`String`	!String::endsWith ic
the field does not end with the given parameter	contains	`String`	String::contains
the field contains the given parameter	notContains	`String`	!String::contains
the field does not contain the given parameter	containsIgnoreCase	`String`	String::contains ic
the field contains the given parameter ignoring case	notContainsIgnoreCase	`String`	!String::contains ic

isEmpty

String

String::isEmpty

the field is empty (i.e. field.length() == 0)

isNotEmpty

String

!String::isEmpty

the field is not empty (i.e. field.length() !=0)

equalIgnoreCase

String

String::equalsIgnoreCase

the field is equal to the given parameter ignoring case

notEqualIgnoreCase

String

!String::equalsIgnoreCase

the field is not equal to the given parameter ignoring case

startsWith

String

String::startsWith

the field starts with the given parameter

notStartsWith

String

!String::startsWith

the field does not start with the given parameter

startsWithIgnoreCase

String

String::startsWith ic

the field starts with the given parameter ignoring case

notStartsWithIgnoreCase

String

!String::startsWith ic

the field does not start with the given parameter ignoring case

endsWith

String

String::endsWith

the field ends with the given parameter

notEndsWith

String

!String::endsWith

the field does not end with the given parameter

endsWithIgnoreCase

String

String::endsWith ic

the field ends with the given parameter

notEndsWithIgnoreCase

String

!String::endsWith ic

the field does not end with the given parameter

contains

String

String::contains

the field contains the given parameter

notContains

String

!String::contains

the field does not contain the given parameter

containsIgnoreCase

String

String::contains ic

the field contains the given parameter ignoring case

notContainsIgnoreCase

String

!String::contains ic

Fields that are null will never fulfill any of the predicates in the list above. Thus, neither contains nor notContains will return true for null values.

A StringField implements the interface traits HasReferenceOperators, HasComparableOperators} and HasStringOperators.

An informal notation of method references is made in the table above with \"!\" indicating the Predicate::negate method. I.e. it means that the operation indicates a Predicate that will return the negated value. The notation \"ic\" means that the method reference shall be applied ignoring case.

Examples

Here is a list with examples for the String Predicates.

isEmpty

The following example that prints the number of films that has a title that is empty (e.g. is equal to ""):

jpaStreamer.stream(Film.class)
    .filter(Film$.title.isEmpty())
    .count();

    System.out.format("There are %d films(s) with an empty title %n", count);