io.questdb.griffin.CharacterStore Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of core Show documentation
QuestDB is High Performance Time Series Database
There is a newer version: 5.0.1
/*******************************************************************************
 *     ___                  _   ____  ____
 *    / _ \ _   _  ___  ___| |_|  _ \| __ )
 *   | | | | | | |/ _ \/ __| __| | | |  _ \
 *   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
 *    \__\_\\__,_|\___||___/\__|____/|____/
 *
 *  Copyright (c) 2014-2019 Appsicle
 *  Copyright (c) 2019-2020 QuestDB
 *
 *  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 io.questdb.griffin;

import io.questdb.log.Log;
import io.questdb.log.LogFactory;
import io.questdb.std.Mutable;
import io.questdb.std.Numbers;
import io.questdb.std.ObjectPool;
import io.questdb.std.str.AbstractCharSequence;
import io.questdb.std.str.AbstractCharSink;
import io.questdb.std.str.CharSink;

public class CharacterStore extends AbstractCharSink implements CharacterStoreEntry, Mutable {
    private static final Log LOG = LogFactory.getLog(CharacterStore.class);
    private final ObjectPool csPool;
    private int capacity;
    private char[] chars;
    private int size = 0;
    private NameAssemblerCharSequence next = null;

    public CharacterStore(int capacity, int poolCapacity) {
        this.capacity = capacity;
        this.chars = new char[Numbers.ceilPow2(capacity)];
        csPool = new ObjectPool<>(NameAssemblerCharSequence::new, poolCapacity);
    }

    @Override
    public int length() {
        return size;
    }

    @Override
    public CharSequence toImmutable() {
        next.hi = size;
        return next;
    }

    public void trimTo(int size) {
        this.size = size;
    }

    public CharacterStoreEntry newEntry() {
        this.next = csPool.next();
        this.next.lo = size;
        return this;
    }

    @Override
    public CharSink put(CharSequence cs) {
        assert cs != null;
        return put(cs, 0, cs.length());
    }

    @Override
    public CharSink put(CharSequence cs, int lo, int hi) {
        for (int i = lo; i < hi; i++) {
            put(cs.charAt(i));
        }
        return this;
    }

    @Override
    public CharSink put(char c) {
        if (size < capacity) {
            chars[size++] = c;
        } else {
            resizeAndPut(c);
        }
        return this;
    }

    @Override
    public CharSink put(char[] chars, int start, int len) {
        for (int i = 0; i < len; i++) {
            put(chars[start + i]);
        }
        return this;
    }

    private void resizeAndPut(char c) {
        char[] next = new char[capacity * 2];
        System.arraycopy(chars, 0, next, 0, capacity);
        chars = next;
        capacity *= 2;
        chars[size++] = c;
        LOG.info().$("resize [capacity=").$(capacity).$(']').$();
    }

    @Override
    public void clear() {
        csPool.clear();
        size = 0;
        next = null;
    }

    public class NameAssemblerCharSequence extends AbstractCharSequence implements Mutable {
        int lo;
        int hi;

        @Override
        public void clear() {
        }

        @Override
        public int length() {
            return hi - lo;
        }

        @Override
        public char charAt(int index) {
            return chars[lo + index];
        }

        @Override
        public CharSequence subSequence(int start, int end) {
            NameAssemblerCharSequence that = csPool.next();
            that.lo = lo + start;
            that.hi = lo + end;
            assert that.lo < that.hi;
            return that;
        }
    }
}