com.px100systems.data.core.CompoundIndexDescriptor.java Source code

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Here is the source code for com.px100systems.data.core.CompoundIndexDescriptor.java

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/*
 * This file is part of Px100 Data.
 *
 * Px100 Data is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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 General Public License for more details.
    
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/
 */
package com.px100systems.data.core;

import com.px100systems.util.PropertyAccessor;
import org.springframework.util.ReflectionUtils;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * Compound index desciptor.<br>
 *
 * @version 0.3 <br>Copyright (c) 2015 Px100 Systems. All Rights Reserved.<br>
 * @author Alex Rogachevsky
 */
public class CompoundIndexDescriptor {
    private String name;

    public static class Field {
        private String name;
        private Class<?> type;
        private boolean descending;

        public Field(String name, Class<?> type, boolean descending) {
            this.descending = descending;
            this.name = name;
            this.type = type;
        }

        public boolean isDescending() {
            return descending;
        }

        public String getName() {
            return name;
        }

        public Class<?> getType() {
            return type;
        }
    }

    private List<Field> fields = new ArrayList<>();

    private static final String NAME_PREFIX = "px100_compound_";

    public static boolean isCompondIndexName(String s) {
        return s.startsWith(NAME_PREFIX);
    }

    public CompoundIndexDescriptor(Class<?> entityClass, String name, String[] fields) {
        if (name.trim().isEmpty())
            throw new RuntimeException("Empty compound index name in " + entityClass.getSimpleName());

        this.name = NAME_PREFIX + entityClass.getSimpleName() + "_" + name + "_idx";

        for (String field : fields) {
            String[] s = field.split(" ");
            if (s.length != 2)
                throw new RuntimeException("Invalid compound index " + name + " in " + entityClass.getSimpleName()
                        + ": couldn't parse field '" + field + "'");

            Method getter = ReflectionUtils.findMethod(entityClass, PropertyAccessor.methodName("get", s[0]));
            if (getter == null)
                throw new RuntimeException("Invalid compound index " + name + " in " + entityClass.getSimpleName()
                        + ": couldn't find getter for '" + field + "'");
            Class<?> returnType = getter.getReturnType();
            if (!returnType.equals(Integer.class) && !returnType.equals(Long.class)
                    && !returnType.equals(Double.class) && !returnType.equals(Date.class)
                    && !returnType.equals(String.class) && !returnType.equals(Boolean.class))
                throw new RuntimeException("Invalid compound index " + name + " in " + entityClass.getSimpleName()
                        + ": field '" + field
                        + "' - only Integer, Long, Double, Date, String, and Boolean are supported");

            this.fields.add(new Field(s[0], returnType, s[1].equalsIgnoreCase("DESC")));
        }
    }

    public List<Field> getFields() {
        return fields;
    }

    public String getName() {
        return name;
    }
}