javafx.beans.binding.BooleanExpression Maven / Gradle / Ivy
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package javafx.beans.binding;
import javafx.beans.value.ObservableBooleanValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import com.sun.javafx.binding.StringFormatter;
import javafx.beans.value.ObservableValue;
/**
* {@code BooleanExpression} is an
* {@link javafx.beans.value.ObservableBooleanValue} plus additional convenience
* methods to generate bindings in a fluent style.
*
* A concrete sub-class of {@code BooleanExpression} has to implement the method
* {@link javafx.beans.value.ObservableBooleanValue#get()}, which provides the
* actual value of this expression.
* @since JavaFX 2.0
*/
public abstract class BooleanExpression implements ObservableBooleanValue {
/**
* Sole constructor
*/
public BooleanExpression() {
}
@Override
public Boolean getValue() {
return get();
}
/**
* Returns a {@code BooleanExpression} that wraps a
* {@link javafx.beans.value.ObservableBooleanValue}. If the
* {@code ObservableBooleanValue} is already a {@code BooleanExpression}, it
* will be returned. Otherwise a new
* {@link javafx.beans.binding.BooleanBinding} is created that is bound to
* the {@code ObservableBooleanValue}.
*
* @param value
* The source {@code ObservableBooleanValue}
* @return A {@code BooleanExpression} that wraps the
* {@code ObservableBooleanValue} if necessary
* @throws NullPointerException
* if {@code value} is {@code null}
*/
public static BooleanExpression booleanExpression(
final ObservableBooleanValue value) {
if (value == null) {
throw new NullPointerException("Value must be specified.");
}
return (value instanceof BooleanExpression) ? (BooleanExpression) value
: new BooleanBinding() {
{
super.bind(value);
}
@Override
public void dispose() {
super.unbind(value);
}
@Override
protected boolean computeValue() {
return value.get();
}
@Override
public ObservableList getDependencies() {
return FXCollections.singletonObservableList(value);
}
};
}
/**
* Returns a {@code BooleanExpression} that wraps an
* {@link javafx.beans.value.ObservableValue}. If the
* {@code ObservableValue} is already a {@code BooleanExpression}, it
* will be returned. Otherwise a new
* {@link javafx.beans.binding.BooleanBinding} is created that is bound to
* the {@code ObservableValue}.
*
* Note: null values will be interpreted as "false".
*
* @param value
* The source {@code ObservableValue}
* @return A {@code BooleanExpression} that wraps the
* {@code ObservableValue} if necessary
* @throws NullPointerException
* if {@code value} is {@code null}
* @since JavaFX 8.0
*/
public static BooleanExpression booleanExpression(final ObservableValue value) {
if (value == null) {
throw new NullPointerException("Value must be specified.");
}
return (value instanceof BooleanExpression) ? (BooleanExpression) value
: new BooleanBinding() {
{
super.bind(value);
}
@Override
public void dispose() {
super.unbind(value);
}
@Override
protected boolean computeValue() {
final Boolean val = value.getValue();
return val == null ? false : val;
}
@Override
public ObservableList> getDependencies() {
return FXCollections.singletonObservableList(value);
}
};
}
/**
* Creates a new {@code BooleanExpression} that performs the conditional
* AND-operation on this {@code BooleanExpression} and a
* {@link ObservableBooleanValue}.
*
* @param other
* the other {@code ObservableBooleanValue}
* @return the new {@code BooleanExpression}
* @throws NullPointerException
* if {@code other} is {@code null}
*/
public BooleanBinding and(final ObservableBooleanValue other) {
return Bindings.and(this, other);
}
/**
* Creates a new {@code BooleanExpression} that performs the conditional
* OR-operation on this {@code BooleanExpression} and a
* {@link ObservableBooleanValue}.
*
* @param other
* the other {@code ObservableBooleanValue}
* @return the new {@code BooleanExpression}
* @throws NullPointerException
* if {@code other} is {@code null}
*/
public BooleanBinding or(final ObservableBooleanValue other) {
return Bindings.or(this, other);
}
/**
* Creates a new {@code BooleanExpression} that calculates the negation of
* this {@code BooleanExpression}.
*
* @return the new {@code BooleanExpression}
*/
public BooleanBinding not() {
return Bindings.not(this);
}
/**
* Creates a new {@code BooleanExpression} that holds {@code true} if this and
* another {@link javafx.beans.value.ObservableBooleanValue} are equal.
*
* @param other
* the other {@code ObservableBooleanValue}
* @return the new {@code BooleanExpression}
* @throws NullPointerException
* if {@code other} is {@code null}
*/
public BooleanBinding isEqualTo(final ObservableBooleanValue other) {
return Bindings.equal(this, other);
}
/**
* Creates a new {@code BooleanExpression} that holds {@code true} if this and
* another {@link javafx.beans.value.ObservableBooleanValue} are equal.
*
* @param other
* the other {@code ObservableBooleanValue}
* @return the new {@code BooleanExpression}
* @throws NullPointerException
* if {@code other} is {@code null}
*/
public BooleanBinding isNotEqualTo(final ObservableBooleanValue other) {
return Bindings.notEqual(this, other);
}
/**
* Creates a {@link javafx.beans.binding.StringBinding} that holds the value
* of this {@code BooleanExpression} turned into a {@code String}. If the
* value of this {@code BooleanExpression} changes, the value of the
* {@code StringBinding} will be updated automatically.
*
* @return the new {@code StringBinding}
*/
public StringBinding asString() {
return (StringBinding) StringFormatter.convert(this);
}
/**
* Creates an {@link javafx.beans.binding.ObjectExpression} that holds the value
* of this {@code BooleanExpression}. If the
* value of this {@code BooleanExpression} changes, the value of the
* {@code ObjectExpression} will be updated automatically.
*
* @return the new {@code ObjectExpression}
* @since JavaFX 8.0
*/
public ObjectExpression asObject() {
return new ObjectBinding() {
{
bind(BooleanExpression.this);
}
@Override
public void dispose() {
unbind(BooleanExpression.this);
}
@Override
protected Boolean computeValue() {
return BooleanExpression.this.getValue();
}
};
}
}