/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.tajo.util;
import java.nio.ByteBuffer;
import java.util.Arrays;
public class BitArray {
private byte [] data;
private int length;
public BitArray(int numBits) {
data = new byte[(int) Math.ceil((double) numBits / 8)];
this.length = numBits;
}
public BitArray(byte [] bytes) {
this.data = bytes;
length = bytes.length * 8;
}
public void set(int idx) {
int offset;
byte dummy;
if (idx >= length)
throw new IllegalArgumentException("length is " + length
+ ", but a given index is " + idx + ".");
offset = idx % 8;
dummy = 1;
dummy <<= 7-offset;
data[idx / 8] |= dummy;
}
public boolean get(int idx) {
int offset;
if(idx >= length)
throw new IllegalArgumentException("length is " + length
+ ", but a given index is " + idx + ".");
offset = idx % 8;
return (((data[idx / 8] >>> 7 - offset) & 1) == 1);
}
public void clear() {
Arrays.fill(data, (byte) 0);
}
public int bytesLength() {
return data.length;
}
public int bitsLength() {
return length;
}
public byte [] toArray() {
return data;
}
public void fromByteBuffer(ByteBuffer byteBuffer) {
clear();
int i = 0;
while(i < data.length && byteBuffer.hasRemaining()) {
data[i] = byteBuffer.get();
i++;
}
}
public String toString() {
StringBuilder sb = new StringBuilder();
for(int i = 0;i < length;i++) {
if(this.get(i))
sb.append("1");
else
sb.append("0");
if (i > 0 && i % 8 == 0) {
sb.append(" ");
}
}
return sb.toString();
}
}