ddf.catalog.validation.impl.validator.RangeValidator.java Source code

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Here is the source code for ddf.catalog.validation.impl.validator.RangeValidator.java

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/**
 * Copyright (c) Codice Foundation
 * <p>
 * This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser
 * General Public License as published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 * <p>
 * This program 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
 * Lesser General Public License for more details. A copy of the GNU Lesser General Public License
 * is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package ddf.catalog.validation.impl.validator;

import java.io.Serializable;
import java.math.BigDecimal;
import java.util.Collections;
import java.util.Optional;

import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;

import com.google.common.base.Preconditions;

import ddf.catalog.data.Attribute;
import ddf.catalog.validation.AttributeValidator;
import ddf.catalog.validation.impl.report.AttributeValidationReportImpl;
import ddf.catalog.validation.impl.violation.ValidationViolationImpl;
import ddf.catalog.validation.report.AttributeValidationReport;
import ddf.catalog.validation.violation.ValidationViolation.Severity;

/**
 * Validates an attribute's value(s) against an <strong>inclusive</strong> numeric range.
 * <p>
 * Is capable of validating {@link Number}s.
 */
public class RangeValidator implements AttributeValidator {
    private static final BigDecimal DEFAULT_EPSILON = new BigDecimal("1E-6");

    private final BigDecimal min;

    private final BigDecimal max;

    /**
     * Creates a {@code RangeValidator} with an <strong>inclusive</strong> range.
     * <p>
     * Uses an epsilon of 1e-6 on both sides of the range to account for floating point
     * representation inaccuracies, so the range is really [min - epsilon, max + epsilon].
     *
     * @param min the minimum allowable value (inclusive), cannot be null
     * @param max the maximum allowable value (inclusive), cannot be null and must be greater than
     *            {@code min}
     * @throws IllegalArgumentException if {@code max} is not greater than {@code min} or either is
     *                                  null
     */
    public RangeValidator(final BigDecimal min, final BigDecimal max) {
        this(min, max, DEFAULT_EPSILON);
    }

    /**
     * Creates a {@code RangeValidator} with an <strong>inclusive</strong> range and the provided
     * epsilon.
     * <p>
     * Uses the provided epsilon on both sides of the range to account for floating point
     * representation inaccuracies, so the range is really [min - epsilon, max + epsilon].
     *
     * @param min     the minimum allowable value (inclusive), cannot be null
     * @param max     the maximum allowable value (inclusive), cannot be null and must be greater
     *                than {@code min}
     * @param epsilon the epsilon value, cannot be null and must be positive
     * @throws IllegalArgumentException if {@code max} is not greater than {@code min},
     *                                  {@code epsilon} is not positive, or if any argument is null
     */
    public RangeValidator(final BigDecimal min, final BigDecimal max, final BigDecimal epsilon) {
        Preconditions.checkArgument(min != null, "The minimum cannot be null.");
        Preconditions.checkArgument(max != null, "The maximum cannot be null.");
        Preconditions.checkArgument(epsilon != null, "The epsilon cannot be null.");
        Preconditions.checkArgument(min.compareTo(max) == -1, "The maximum must be greater than the minimum.");
        Preconditions.checkArgument(epsilon.compareTo(BigDecimal.ZERO) == 1, "The epsilon must be greater than 0.");

        this.min = min.subtract(epsilon);
        this.max = max.add(epsilon);
    }

    @Override
    public Optional<AttributeValidationReport> validate(final Attribute attribute) {
        Preconditions.checkArgument(attribute != null, "The attribute cannot be null.");

        final String name = attribute.getName();

        for (final Serializable value : attribute.getValues()) {
            final BigDecimal bdValue;
            if (value instanceof Number) {
                bdValue = new BigDecimal(value.toString());
            } else {
                continue;
            }

            if (!checkRange(bdValue)) {
                final String violationMessage = String.format("%s must be between %s and %s", name,
                        min.toPlainString(), max.toPlainString());
                final AttributeValidationReportImpl report = new AttributeValidationReportImpl();
                report.addViolation(
                        new ValidationViolationImpl(Collections.singleton(name), violationMessage, Severity.ERROR));
                return Optional.of(report);
            }
        }

        return Optional.empty();
    }

    private boolean checkRange(final BigDecimal value) {
        return min.compareTo(value) <= 0 && value.compareTo(max) <= 0;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }

        if (o == null || getClass() != o.getClass()) {
            return false;
        }

        RangeValidator that = (RangeValidator) o;

        return new EqualsBuilder().append(min, that.min).append(max, that.max).isEquals();
    }

    @Override
    public int hashCode() {
        return new HashCodeBuilder(17, 41).append(min).append(max).toHashCode();
    }
}