com.github.britter.beanvalidators.EmptyConstraintValidator.java Source code

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Here is the source code for com.github.britter.beanvalidators.EmptyConstraintValidator.java

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/*
 * Copyright 2015 Benedikt Ritter
 *
 * 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 com.github.britter.beanvalidators;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import javax.validation.ValidationException;
import java.lang.reflect.Array;
import java.util.Collection;
import java.util.Map;

import org.apache.commons.lang3.StringUtils;

public class EmptyConstraintValidator implements ConstraintValidator<Empty, Object> {

    @Override
    public void initialize(final Empty constraintAnnotation) {
    }

    @Override
    public boolean isValid(final Object value, final ConstraintValidatorContext context) {
        if (value == null) {
            return true;
        } else if (value instanceof String) {
            return StringUtils.isEmpty((String) value);
        } else if (value instanceof Collection) {
            return ((Collection) value).isEmpty();
        } else if (value instanceof Map) {
            return ((Map) value).isEmpty();
        } else if (value.getClass().isArray()) {
            return Array.getLength(value) == 0;
        } else {
            // Is this the correct behavior?
            throw new ValidationException("@Empty can not be applied to objects of type " + value.getClass());
        }
    }

}