CompactStringBuffer.java
/**
* Copyright (c) 2018, RTE (http://www.rte-france.com)
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
* SPDX-License-Identifier: MPL-2.0
*/
package com.powsybl.timeseries;
import com.google.common.math.IntMath;
import java.nio.ByteBuffer;
import java.nio.IntBuffer;
import java.util.Objects;
import java.util.function.IntFunction;
/**
* @author Geoffroy Jamgotchian {@literal <geoffroy.jamgotchian at rte-france.com>}
*/
public class CompactStringBuffer {
private final IntBuffer buffer;
private final BiList<String> dict = new BiList<>();
public CompactStringBuffer(IntFunction<ByteBuffer> byteBufferAllocator, int size) {
Objects.requireNonNull(byteBufferAllocator);
if (size < 0) {
throw new IllegalArgumentException("Invalid buffer size: " + size);
}
this.buffer = byteBufferAllocator.apply(IntMath.checkedMultiply(size, Integer.BYTES)).asIntBuffer();
}
public void putString(int index, String value) {
int num;
if (value == null) {
num = 0;
} else {
num = dict.addIfNotAlreadyExist(value) + 1;
}
buffer.put(index, num);
}
public String getString(int index) {
int num = buffer.get(index);
if (num == 0) {
return null;
} else {
return dict.get(num - 1);
}
}
public int capacity() {
return buffer.capacity();
}
public String[] toArray() {
String[] array = new String[buffer.capacity()];
for (int i = 0; i < buffer.capacity(); i++) {
array[i] = getString(i);
}
return array;
}
}