98 lines
2.7 KiB
Java
98 lines
2.7 KiB
Java
/*******************************************************************************
|
|
* Copyright (c) 2002 - 2006 IBM Corporation.
|
|
* All rights reserved. This program and the accompanying materials
|
|
* are made available under the terms of the Eclipse Public License v1.0
|
|
* which accompanies this distribution, and is available at
|
|
* http://www.eclipse.org/legal/epl-v10.html
|
|
*
|
|
* Contributors:
|
|
* IBM Corporation - initial API and implementation
|
|
*******************************************************************************/
|
|
package com.ibm.wala.util.intset;
|
|
|
|
import java.io.Serializable;
|
|
|
|
|
|
/**
|
|
* an int vector implementation designed for low occupancy. Note that get() from
|
|
* this vector is a binary search.
|
|
*
|
|
* This should only be used for small sets ... insertion and deletion are linear
|
|
* in size of set.
|
|
*/
|
|
public class SparseIntVector implements IntVector, Serializable {
|
|
|
|
private static final long serialVersionUID = -2428993854689991888L;
|
|
private final static int INITIAL_SIZE = 5;
|
|
private final double EXPANSION = 1.5;
|
|
int maxIndex = -1;
|
|
|
|
/**
|
|
* if indices[i] = x, then data[i] == get(x)
|
|
*/
|
|
final private MutableSparseIntSet indices = MutableSparseIntSet.makeEmpty();
|
|
private int[] data = new int[INITIAL_SIZE];
|
|
|
|
private final int defaultValue;
|
|
|
|
public SparseIntVector(int defaultValue) {
|
|
this.defaultValue = defaultValue;
|
|
}
|
|
|
|
/*
|
|
* @see com.ibm.wala.util.intset.IntVector#get(int)
|
|
*/
|
|
@Override
|
|
public int get(int x) {
|
|
int index = indices.getIndex(x);
|
|
if (index == -1) {
|
|
return defaultValue;
|
|
} else {
|
|
return data[index];
|
|
}
|
|
}
|
|
|
|
/*
|
|
* TODO: this can be optimized
|
|
*
|
|
* @see com.ibm.wala.util.intset.IntVector#set(int, int)
|
|
*/
|
|
@Override
|
|
public void set(int x, int value) {
|
|
maxIndex = Math.max(maxIndex,x);
|
|
int index = indices.getIndex(x);
|
|
if (index == -1) {
|
|
indices.add(x);
|
|
index = indices.getIndex(x);
|
|
ensureCapacity(indices.size() + 1);
|
|
if (index < (data.length - 1)) {
|
|
System.arraycopy(data, index, data, index + 1, indices.size() - index);
|
|
}
|
|
}
|
|
data[index] = value;
|
|
}
|
|
|
|
private void ensureCapacity(int capacity) {
|
|
if (data.length < capacity + 1) {
|
|
int[] old = data;
|
|
data = new int[1 + (int) (capacity * EXPANSION)];
|
|
System.arraycopy(old, 0, data, 0, old.length);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* @see com.ibm.wala.util.debug.VerboseAction#performVerboseAction()
|
|
*/
|
|
public void performVerboseAction() {
|
|
System.err.println((getClass() + " stats: "));
|
|
System.err.println(("data.length " + data.length));
|
|
System.err.println(("indices.size() " + indices.size()));
|
|
}
|
|
|
|
|
|
@Override
|
|
public int getMaxIndex() {
|
|
return maxIndex;
|
|
}
|
|
}
|