org.springframework.data.solr.core.query.SimplePivotField.java Source code

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Here is the source code for org.springframework.data.solr.core.query.SimplePivotField.java

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/*
 * Copyright 2012 - 2018 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
 *
 * https://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.springframework.data.solr.core.query;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.springframework.lang.Nullable;
import org.springframework.util.Assert;

/**
 * The most trivial implementation of {@link PivotField}.
 *
 * @author Francisco Spaeth
 * @author Christoph Strobl
 */
public class SimplePivotField implements PivotField {

    private static final String DELIMINATOR = ",";
    private final List<Field> fields = new ArrayList<>(2);
    private @Nullable String name;

    /**
     * Create new {@link SimplePivotField}
     *
     * @param fieldnames must consist of at least 2 fieldname eg. {@code "field_1", "field_2"} or a single String with
     *          comma separated fieldnames like {@code "field_1,field_2"}
     */
    public SimplePivotField(String... fieldnames) {
        Assert.noNullElements(fieldnames, "Fieldnames must not contain null values");
        splitAndAddFieldnames(fieldnames);
        Assert.state(fields.size() > 1, "2 or more fields required for pivot facets");
    }

    /**
     * @param fields must consist of a least 2 {@link Field}s.
     */
    public SimplePivotField(List<Field> fields) {
        Assert.notNull(fields, "Fields should not be null");
        Assert.isTrue(fields.size() > 1, "A pivot field needs to be composed by 2 or more solr fields");

        this.fields.addAll(fields);
    }

    private void splitAndAddFieldnames(String... fieldnames) {
        for (String fieldname : fieldnames) {
            if (fieldname.contains(DELIMINATOR)) {
                splitAndAddFieldnames(fieldname.split(DELIMINATOR));
            } else {
                this.fields.add(new SimpleField(fieldname));
            }
        }
    }

    @Override
    public List<Field> getFields() {
        return Collections.unmodifiableList(fields);
    }

    @Override
    public String getName() {
        if (this.name == null) {
            this.name = ectractFieldName();
        }
        return this.name;
    }

    private String ectractFieldName() {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < fields.size(); i++) {
            if (i > 0) {
                sb.append(DELIMINATOR);
            }
            sb.append(fields.get(i).getName());
        }
        return sb.toString();
    }

    @Override
    public String toString() {
        return getName();
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((getName() == null) ? 0 : getName().hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        SimplePivotField other = (SimplePivotField) obj;
        if (getName() == null) {
            if (other.getName() != null) {
                return false;
            }
        } else if (!getName().equals(other.getName())) {
            return false;
        }
        return true;
    }

}