hashutilities.cs

来自「ajax patterns 这是关于ajax设计模式方面的原代码」· CS 代码 · 共 252 行

/*
    Copyright 2006 Christian Gross http://www.devspace.com
    From the book Ajax Patterns and Best Practices

   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.
*/
using System;

namespace Devspace.Commons.Automaters {
    // Borrowed code from Jakarta Commons
    public class HashCodeAutomater {
        private readonly int _constant;
        private int _runningTotal;
            
        public HashCodeAutomater() {
            _constant = 37;
            _runningTotal = 17;
        }
        
        public HashCodeAutomater(int initialNonZeroOddNumber, int multiplierNonZeroOddNumber) {
            if (initialNonZeroOddNumber == 0) {
                throw new ArgumentOutOfRangeException( "HashCodeBuilder requires a non zero initial value");
            }
            if (initialNonZeroOddNumber % 2 == 0) {
                throw new ArgumentOutOfRangeException("HashCodeBuilder requires an odd initial value");
            }
            if (multiplierNonZeroOddNumber == 0) {
                throw new ArgumentOutOfRangeException("HashCodeBuilder requires a non zero multiplier");
            }
            if (multiplierNonZeroOddNumber % 2 == 0) {
                throw new ArgumentOutOfRangeException("HashCodeBuilder requires an odd multiplier");
            }
            _constant = multiplierNonZeroOddNumber;
            _runningTotal = initialNonZeroOddNumber;
        }
        

        public HashCodeAutomater AppendSuper(int superHashCode) {
            _runningTotal = _runningTotal * _runningTotal + superHashCode;
            return this;
        }

        public HashCodeAutomater Append( Object obj) {
            if (obj == null) {
                _runningTotal = _runningTotal * _constant;
                
            } else {
                if( obj.GetType().IsArray == false) {
                    _runningTotal = _runningTotal * _runningTotal + obj.GetHashCode();
                    
                } else {
                    //'Switch' on type of array, to dispatch to the correct handler
                    // This handles multi dimensional arrays
                    if (obj is long[]) {
                        Append((long[]) obj);
                    }
                    else if (obj is int[]) {
                        Append((int[]) obj);
                    }
                    else if (obj is short[]) {
                        Append((short[]) obj);
                    }
                    else if (obj is char[]) {
                        Append((char[]) obj);
                    }
                    else if (obj is byte[]) {
                        Append((byte[]) obj);
                    }
                    else if (obj is double[]) {
                        Append((double[]) obj);
                    }
                    else if (obj is float[]) {
                        Append((float[]) obj);
                    }
                    else if (obj is bool[]) {
                        Append((bool[]) obj);
                    }
                    else {
                        // Not an array of primitives
                        Append((Object[]) obj);
                    }
                }
            }
            return this;
        }

        public HashCodeAutomater Append(long value) {
            _runningTotal = _runningTotal * _constant + ((int) (value ^ (value >> 32)));
            return this;
        }
        
        public HashCodeAutomater Append(int value) {
            _runningTotal = _runningTotal * _constant + value;
            return this;
        }
        
        public HashCodeAutomater Append(short value) {
            _runningTotal = _runningTotal * _constant + value;
            return this;
        }
        
        public HashCodeAutomater Append(char value) {
            _runningTotal = _runningTotal * _constant + value;
            return this;
        }
        
        public HashCodeAutomater Append(byte value) {
            _runningTotal = _runningTotal * _constant + value;
            return this;
        }
        
        public HashCodeAutomater Append(double value) {
            return Append( BitConverter.DoubleToInt64Bits( value));
        }
        
        public HashCodeAutomater Append(float value) {
            _runningTotal = _runningTotal * _constant + Convert.ToInt32( value);
            return this;
        }
        
        public HashCodeAutomater Append(bool value) {
            _runningTotal = _runningTotal * _constant + (value ? 0 : 1);
            return this;
        }
        
        public HashCodeAutomater Append(Object[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }

        public HashCodeAutomater Append(long[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public HashCodeAutomater Append(int[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public HashCodeAutomater Append(short[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public HashCodeAutomater Append(char[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public HashCodeAutomater Append(byte[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public HashCodeAutomater Append(double[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public HashCodeAutomater Append(float[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public HashCodeAutomater Append(bool[] array) {
            if (array == null) {
                _runningTotal = _runningTotal * _constant;
            }
            else {
                for (int i = 0; i < array.Length; i++) {
                    Append(array[i]);
                }
            }
            return this;
        }
        
        public int toHashCode() {
            return _runningTotal;
        }
    }
}