nz.co.testamation.common.contract.Conditions.java Source code

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Here is the source code for nz.co.testamation.common.contract.Conditions.java

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/*
 * Copyright 2016 Ratha Long
 *
 * 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.
 */

package nz.co.testamation.common.contract;

import com.google.common.collect.Iterables;
import org.apache.commons.lang3.StringUtils;

public class Conditions {
    public static void ensureTrue(boolean condition) {
        ensureTrue(condition, "Expected condition to be true but was false");
    }

    public static void ensureTrue(boolean condition, String message) {
        if (!condition) {
            throw new IllegalStateException(message);
        }
    }

    public static <T> T notNull(T notNull, String message) {
        if (notNull == null) {
            throw new IllegalStateException(message);
        }
        return notNull;
    }

    public static <T> T notNull(T notNull) {
        return notNull(notNull, "Expected argument to not be null");
    }

    public static void ensureNull(Object obj) {
        ensureNull(obj, "Expected argument to be null");
    }

    public static void ensureNull(Object obj, String message) {
        if (obj != null) {
            throw new IllegalStateException(message);
        }
    }

    public static void ensureFalse(boolean condition) {
        if (condition) {
            throw new IllegalStateException("Expected condition to be false but was true");
        }
    }

    public static <T> T notEmpty(T obj) {
        if (obj instanceof CharSequence && StringUtils.isBlank((CharSequence) obj)) {
            throw new IllegalStateException("Expected char sequence to not be empty");
        }

        if (obj instanceof Iterable && Iterables.isEmpty((Iterable<?>) obj)) {
            throw new IllegalStateException("Expected iterable to not be empty");
        }

        return Conditions.notNull(obj);
    }

    public static void ensureAllNotNull(Object... objects) {
        for (Object object : objects) {
            notNull(object);
        }
    }

    public static void ensureAllTrue(boolean... conditions) {
        for (boolean condition : conditions) {
            ensureTrue(condition);
        }
    }
}