IntComparatorChain.java

package com.github.lwhite1.tablesaw.util;

/**
 *
 */

import it.unimi.dsi.fastutil.ints.IntComparator;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.BitSet;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;

public class IntComparatorChain implements IntComparator, Serializable {

    private static final long serialVersionUID = -721644942746081630L;
    private final List<IntComparator> comparatorChain;
    private BitSet orderingBits;
    private boolean isLocked;

    public IntComparatorChain() {
        this(new ArrayList<>(), new BitSet());
    }

    public IntComparatorChain(IntComparator comparator) {
        this(comparator, false);
    }

    public IntComparatorChain(IntComparator comparator, boolean reverse) {
        this.orderingBits = null;
        this.isLocked = false;
        this.comparatorChain = new ArrayList<>(1);
        this.comparatorChain.add(comparator);
        this.orderingBits = new BitSet(1);
        if (reverse) {
            this.orderingBits.set(0);
        }

    }

    public IntComparatorChain(List<IntComparator> list) {
        this(list, new BitSet(list.size()));
    }

    public IntComparatorChain(List<IntComparator> list, BitSet bits) {
        this.orderingBits = null;
        this.isLocked = false;
        this.comparatorChain = list;
        this.orderingBits = bits;
    }

    public void addComparator(IntComparator comparator) {
        this.addComparator(comparator, false);
    }

    public void addComparator(IntComparator comparator, boolean reverse) {
        this.checkLocked();
        this.comparatorChain.add(comparator);
        if (reverse) {
            this.orderingBits.set(this.comparatorChain.size() - 1);
        }
    }

    public void setComparator(int index, IntComparator comparator) throws IndexOutOfBoundsException {
        this.setComparator(index, comparator, false);
    }

    public void setComparator(int index, IntComparator comparator, boolean reverse) {
        this.checkLocked();
        this.comparatorChain.set(index, comparator);
        if (reverse) {
            this.orderingBits.set(index);
        } else {
            this.orderingBits.clear(index);
        }
    }

    public void setForwardSort(int index) {
        this.checkLocked();
        this.orderingBits.clear(index);
    }

    public void setReverseSort(int index) {
        this.checkLocked();
        this.orderingBits.set(index);
    }

    public int size() {
        return this.comparatorChain.size();
    }

    public boolean isLocked() {
        return this.isLocked;
    }

    private void checkLocked() {
        if (this.isLocked) {
            throw new UnsupportedOperationException("Comparator ordering cannot be changed after the first comparison" +
                    " is " +
                    "performed");
        }
    }

    private void checkChainIntegrity() {
        if (this.comparatorChain.size() == 0) {
            throw new UnsupportedOperationException("ComparatorChains must contain at least one Comparator");
        }
    }

    public int compare(Integer o1, Integer o2) throws UnsupportedOperationException {
        if (!this.isLocked) {
            this.checkChainIntegrity();
            this.isLocked = true;
        }

        Iterator comparators = this.comparatorChain.iterator();

        for (int comparatorIndex = 0; comparators.hasNext(); ++comparatorIndex) {
            Comparator comparator = (Comparator) comparators.next();
            int retval = comparator.compare(o1, o2);
            if (retval != 0) {
                if (this.orderingBits.get(comparatorIndex)) {
                    if (retval > 0) {
                        retval = -1;
                    } else {
                        retval = 1;
                    }
                }
                return retval;
            }
        }
        return 0;
    }

    public int compare(int o1, int o2) throws UnsupportedOperationException {
        if (!this.isLocked) {
            this.checkChainIntegrity();
            this.isLocked = true;
        }

        Iterator comparators = this.comparatorChain.iterator();

        for (int comparatorIndex = 0; comparators.hasNext(); ++comparatorIndex) {
            IntComparator comparator = (IntComparator) comparators.next();
            int retval = comparator.compare(o1, o2);
            if (retval != 0) {
                if (this.orderingBits.get(comparatorIndex)) {
                    if (retval > 0) {
                        retval = -1;
                    } else {
                        retval = 1;
                    }
                }
                return retval;
            }
        }
        return 0;
    }

    public int hashCode() {
        int hash = 0;
        if (null != this.comparatorChain) {
            hash ^= this.comparatorChain.hashCode();
        }

        if (null != this.orderingBits) {
            hash ^= this.orderingBits.hashCode();
        }
        return hash;
    }

    public boolean equals(Object object) {
        if (this == object) {
            return true;
        } else if (null == object) {
            return false;
        } else if (!object.getClass().equals(this.getClass())) {
            return false;
        } else {
            boolean var10000;
            label48:
            {
                label32:
                {
                    IntComparatorChain chain = (IntComparatorChain) object;
                    if (null == this.orderingBits) {
                        if (null != chain.orderingBits) {
                            break label32;
                        }
                    } else if (!this.orderingBits.equals(chain.orderingBits)) {
                        break label32;
                    }

                    if (null == this.comparatorChain) {
                        if (null == chain.comparatorChain) {
                            break label48;
                        }
                    } else if (this.comparatorChain.equals(chain.comparatorChain)) {
                        break label48;
                    }
                }

                var10000 = false;
                return var10000;
            }

            var10000 = true;
            return var10000;
        }
    }
}