com.nhaarman.ellie.annotation.Collate Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of core Show documentation
Compile-time active record ORM for Android.
The newest version!
/*
 * Copyright (C) 2014 Michael Pardo
 * Copyright (C) 2014 Niek Haarman
 *
 * 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.nhaarman.ellie.annotation;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.RetentionPolicy.CLASS;

/**
 * 
 * An annotation that indicates a member should define its SQLite column using the COLLATE constraint. Must be
 * used in conjunction with {@link Column}.
 * 
 * 
 * http://www.sqlite.org/datatype3.html#collation
 * 
 * http://www.sqlite.org/syntaxdiagrams.html#column-constraint
 * 
 * 
 */
@Target(FIELD)
@Retention(CLASS)
public @interface Collate {

    /**
     * When SQLite compares two strings, it uses a collating sequence or collating function (two words for the same
     * thing) to determine which string is greater or if the two strings are equal. SQLite has three built-in
     * collating functions: BINARY, NOCASE, and RTRIM.
     */
    public enum CollatingSequence {
        /**
         * Compares string data using memcmp(), regardless of text encoding.
         */
        BINARY("BINARY"),
        /**
         * The same as binary, except the 26 upper case characters of ASCII are folded to their lower case equivalents
         * before the comparison is performed. Note that only ASCII characters are case folded. SQLite does not
         * attempt to do full UTF case folding due to the size of the tables required.
         */
        NOCASE("NOCASE"),
        /**
         * The same as binary, except that trailing space characters are ignored.
         */
        RTRIM("RTRIM");

        private String mKeyword;

        CollatingSequence(String keyword) {
            mKeyword = keyword;
        }

        public String keyword() {
            return mKeyword;
        }
    }

    /**
     * Returns a collating sequence to use for string comparison.
     *
     * @return The collating sequence.
     */
    public CollatingSequence value();
}