Java Object Type Case castOrDefault(Class<T> type, Object value, T defaultValue, boolean allowNull)

Description

Casts a value to another type, returning a default value if the cast is not possible or if the value is null and null values are not allowed.

License

Apache License

Parameter

Parameter	Description
type	the type to which the value should be cast
value	the value to be cast
defaultValue	the default value to be returned if the cast is not possible or if the value is null and null values are not allowed.
allowNull	if false and the value is null, the defaultValue will be returned.
T	the type to which the value should be cast and the type of the defaultValue .

Return

the result of the cast or the defaultValue if the cast is not possible or if the value is null and null values are not allowed.

Declaration

@SuppressWarnings("unchecked")
public static <T> T castOrDefault(Class<T> type, Object value, T defaultValue, boolean allowNull)

Method Source Code

//package com.java2s;
/**/*from   w w w . j  a  v a 2 s.co  m*/
 * Copyright 2015-2016 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Main {
    /**
     * Casts a value to another type, returning a default value if the cast is not possible or if the value is null and null values are not allowed.
     * @param type the type to which the value should be cast
     * @param value the value to be cast
     * @param defaultValue the default value to be returned if the cast is not possible or if the {@code value} is null and null values are not allowed.
     * @param allowNull if false and the {@code value} is null, the {@code defaultValue} will be returned.
     * @param <T> the type to which the value should be cast and the type of the {@code defaultValue}.
     * @return the result of the cast or the {@code defaultValue} if the cast is not possible or if the value is null and null values are not allowed.
     */
    @SuppressWarnings("unchecked")
    public static <T> T castOrDefault(Class<T> type, Object value, T defaultValue, boolean allowNull) {
        if (value == null)
            return allowNull ? null : defaultValue;
        if (!type.isAssignableFrom(value.getClass())) {
            return defaultValue;
        }
        return (T) value;
    }
}

Java Object Type Case castOrDefault(Class type, Object value, T defaultValue, boolean allowNull)