Java tutorial
/* * Copyright (c) 2010, 2017, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javafx.beans.binding; import javafx.beans.value.ObservableStringValue; import javafx.beans.value.ObservableValue; import com.sun.javafx.binding.StringFormatter; /** * {@code StringExpression} is an * {@link javafx.beans.value.ObservableStringValue} plus additional convenience * methods to generate bindings in a fluent style. * <p> * A concrete sub-class of {@code StringExpression} has to implement the method * {@link javafx.beans.value.ObservableStringValue#get()}, which provides the * actual value of this expression. * <p> * Note: all implementation of {@link javafx.beans.binding.BooleanBinding} * returned by the comparisons in this class consider a {@code String} that is * {@code null} equal to an empty {@code String}. * @since JavaFX 2.0 */ public abstract class StringExpression implements ObservableStringValue { @Override public String getValue() { return get(); } /** * Returns usually the value of this {@code StringExpression}. Only if the * value is {@code null} an empty {@code String} is returned instead. * * @return the value of this {@code StringExpression} or the empty * {@code String} */ public final String getValueSafe() { final String value = get(); return value == null ? "" : value; } /** * Returns a {@code StringExpression} that wraps a * {@link javafx.beans.value.ObservableValue}. If the * {@code ObservableValue} is already a {@code StringExpression}, it will be * returned. Otherwise a new {@link javafx.beans.binding.StringBinding} is * created that holds the value of the {@code ObservableValue} converted to * a {@code String}. * * @param value * The source {@code ObservableValue} * @return A {@code StringExpression} that wraps the {@code ObservableValue} * if necessary * @throws NullPointerException * if {@code value} is {@code null} */ public static StringExpression stringExpression(final ObservableValue<?> value) { if (value == null) { throw new NullPointerException("Value must be specified."); } return StringFormatter.convert(value); } /** * Returns a {@code StringExpression} that holds the value of this * {@code StringExpression} concatenated with another {@code Object}. * <p> * If the value of this {@code StringExpression} changes, the value of the * resulting {@code StringExpression} is updated automatically. Also if the * other {@code Object} is an implementation of * {@link javafx.beans.value.ObservableValue}, changes in the other * {@code Object} are reflected automatically in the resulting * {@code StringExpression}. * * @param other * the other {@code Object} * @return the new {@code StringExpression} */ public StringExpression concat(Object other) { return Bindings.concat(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this and another {@link javafx.beans.value.ObservableStringValue} are * equal. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding isEqualTo(final ObservableStringValue other) { return Bindings.equal(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is equal to a constant value. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding isEqualTo(final String other) { return Bindings.equal(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this and another {@link javafx.beans.value.ObservableStringValue} are * not equal. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding isNotEqualTo(final ObservableStringValue other) { return Bindings.notEqual(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is not equal to a constant value. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding isNotEqualTo(final String other) { return Bindings.notEqual(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this and another {@link javafx.beans.value.ObservableStringValue} are * equal ignoring case. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the second {@code ObservableStringValue} * @return the new {@code BooleanBinding} */ public BooleanBinding isEqualToIgnoreCase(final ObservableStringValue other) { return Bindings.equalIgnoreCase(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is equal to a constant value ignoring * case. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding isEqualToIgnoreCase(final String other) { return Bindings.equalIgnoreCase(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this and another {@link javafx.beans.value.ObservableStringValue} are * not equal ignoring case. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the second {@code ObservableStringValue} * @return the new {@code BooleanBinding} */ public BooleanBinding isNotEqualToIgnoreCase(final ObservableStringValue other) { return Bindings.notEqualIgnoreCase(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is not equal to a constant value * ignoring case. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding isNotEqualToIgnoreCase(final String other) { return Bindings.notEqualIgnoreCase(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is greater than another * {@link javafx.beans.value.ObservableStringValue}. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the second {@code ObservableStringValue} * @return the new {@code BooleanBinding} */ public BooleanBinding greaterThan(final ObservableStringValue other) { return Bindings.greaterThan(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is greater than a constant value. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding greaterThan(final String other) { return Bindings.greaterThan(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is less than another * {@link javafx.beans.value.ObservableStringValue}. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the second {@code ObservableStringValue} * @return the new {@code BooleanBinding} */ public BooleanBinding lessThan(final ObservableStringValue other) { return Bindings.lessThan(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is less than a constant value. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding lessThan(final String other) { return Bindings.lessThan(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is greater than or equal to another * {@link javafx.beans.value.ObservableStringValue}. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the second {@code ObservableStringValue} * @return the new {@code BooleanBinding} */ public BooleanBinding greaterThanOrEqualTo(final ObservableStringValue other) { return Bindings.greaterThanOrEqual(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is greater than or equal to a constant * value. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding greaterThanOrEqualTo(final String other) { return Bindings.greaterThanOrEqual(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is less than or equal to another * {@link javafx.beans.value.ObservableStringValue}. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the second {@code ObservableStringValue} * @return the new {@code BooleanBinding} */ public BooleanBinding lessThanOrEqualTo(final ObservableStringValue other) { return Bindings.lessThanOrEqual(this, other); } /** * Creates a new {@link javafx.beans.binding.BooleanBinding} that holds {@code true} * if this {@code StringExpression} is less than or equal to a constant * value. * <p> * Note: In this comparison a {@code String} that is {@code null} is * considered equal to an empty {@code String}. * * @param other * the constant value * @return the new {@code BooleanBinding} */ public BooleanBinding lessThanOrEqualTo(final String other) { return Bindings.lessThanOrEqual(this, other); } /** * Creates a new {@link BooleanBinding} that holds {@code true} if this * {@code StringExpression} is {@code null}. * * @return the new {@code BooleanBinding} */ public BooleanBinding isNull() { return Bindings.isNull(this); } /** * Creates a new {@link BooleanBinding} that holds {@code true} if this * {@code StringExpression} is not {@code null}. * * @return the new {@code BooleanBinding} */ public BooleanBinding isNotNull() { return Bindings.isNotNull(this); } /** * Creates a new {@link IntegerBinding} that holds the length of this * {@code StringExpression}. * <p> * Note: If the value of this {@code StringExpression} is {@code null}, * the length is considered to be {@code 0}. * * @return the new {@code IntegerBinding} * @since JavaFX 8.0 */ public IntegerBinding length() { return Bindings.length(this); } /** * Creates a new {@link BooleanBinding} that holds {@code true} if this * {@code StringExpression} is empty. * <p> * Note: If the value of this {@code StringExpression} is {@code null}, * it is considered to be empty. * * @return the new {@code BooleanBinding} * @since JavaFX 8.0 */ public BooleanBinding isEmpty() { return Bindings.isEmpty(this); } /** * Creates a new {@link BooleanBinding} that holds {@code true} if this * {@code StringExpression} is not empty. * <p> * Note: If the value of this {@code StringExpression} is {@code null}, * it is considered to be empty. * * @return the new {@code BooleanBinding} * @since JavaFX 8.0 */ public BooleanBinding isNotEmpty() { return Bindings.isNotEmpty(this); } }