NullArgumentException.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */
package org.apache.commons.math4.legacy.exception;

import org.apache.commons.math4.legacy.exception.util.ExceptionContext;
import org.apache.commons.math4.legacy.exception.util.ExceptionContextProvider;
import org.apache.commons.math4.legacy.exception.util.Localizable;
import org.apache.commons.math4.legacy.exception.util.LocalizedFormats;

/**
 * All conditions checks that fail due to a {@code null} argument must throw
 * this exception.
 * This class is meant to signal a precondition violation ("null is an illegal
 * argument") and so does not extend the standard {@code NullPointerException}.
 * Propagation of {@code NullPointerException} from within Commons-Math is
 * construed to be a bug.
 * <p>
 * Note: from 4.0 onwards, this class extends {@link NullPointerException} instead
 * of {@link MathIllegalArgumentException}.
 *
 * @since 2.2
 */
public class NullArgumentException extends NullPointerException
    implements ExceptionContextProvider {

    /** Serializable version Id. */
    private static final long serialVersionUID = 20150225L;

    /** Context. */
    private final ExceptionContext context;

    /**
     * Default constructor.
     */
    public NullArgumentException() {
        this(LocalizedFormats.NULL_NOT_ALLOWED);
    }
    /**
     * @param pattern Message pattern providing the specific context of
     * the error.
     * @param arguments Values for replacing the placeholders in {@code pattern}.
     */
    public NullArgumentException(Localizable pattern,
                                 Object... arguments) {
        context = new ExceptionContext(this);
        context.addMessage(pattern, arguments);
    }

    /**
     * {@inheritDoc}
     * @since 4.0
     */
    @Override
    public ExceptionContext getContext() {
        return context;
    }

    /** {@inheritDoc} */
    @Override
    public String getMessage() {
        return context.getMessage();
    }

    /** {@inheritDoc} */
    @Override
    public String getLocalizedMessage() {
        return context.getLocalizedMessage();
    }

    /**
     * Checks that an object is not null.
     *
     * @param o Object to be checked.
     * @param pattern Message pattern.
     * @param args Arguments to replace the placeholders in {@code pattern}.
     * @throws NullArgumentException if {@code o} is {@code null}.
     */
    public static void check(Object o,
                             Localizable pattern,
                             Object... args) {
        if (o == null) {
            throw new NullArgumentException(pattern, args);
        }
    }

    /**
     * Checks that an object is not null.
     *
     * @param o Object to be checked.
     * @throws NullArgumentException if {@code o} is {@code null}.
     */
    public static void check(Object o) {
        if (o == null) {
            throw new NullArgumentException();
        }
    }
}