A mutable int wrapper.
/*
* 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.
*/
// Rwevised from commons lang Apache
/**
* A mutable <code>int</code> wrapper.
*
* @see Integer
* @since 2.1
* @version $Id: MutableInt.java 437554 2006-08-28 06:21:41Z bayard $
*/
public class MutableInt extends Number implements Comparable, Mutable {
/**
* Required for serialization support.
*
* @see java.io.Serializable
*/
private static final long serialVersionUID = 512176391864L;
/** The mutable value. */
private int value;
/**
* Constructs a new MutableInt with the default value of zero.
*/
public MutableInt() {
super();
}
/**
* Constructs a new MutableInt with the specified value.
*
* @param value
* a value.
*/
public MutableInt(int value) {
super();
this.value = value;
}
/**
* Constructs a new MutableInt with the specified value.
*
* @param value
* a value.
* @throws NullPointerException
* if the object is null
*/
public MutableInt(Number value) {
super();
this.value = value.intValue();
}
//-----------------------------------------------------------------------
/**
* Gets the value as a Integer instance.
*
* @return the value as a Integer
*/
public Object getValue() {
return new Integer(this.value);
}
/**
* Sets the value.
*
* @param value
* the value to set
*/
public void setValue(int value) {
this.value = value;
}
/**
* Sets the value from any Number instance.
*
* @param value
* the value to set
* @throws NullPointerException
* if the object is null
* @throws ClassCastException
* if the type is not a {@link Number}
*/
public void setValue(Object value) {
setValue(((Number) value).intValue());
}
//-----------------------------------------------------------------------
/**
* Increments the value.
*
* @since Commons Lang 2.2
*/
public void increment() {
value++;
}
/**
* Decrements the value.
*
* @since Commons Lang 2.2
*/
public void decrement() {
value--;
}
//-----------------------------------------------------------------------
/**
* Adds a value.
*
* @param operand
* the value to add
*
* @since Commons Lang 2.2
*/
public void add(int operand) {
this.value += operand;
}
/**
* Adds a value.
*
* @param operand
* the value to add
* @throws NullPointerException
* if the object is null
*
* @since Commons Lang 2.2
*/
public void add(Number operand) {
this.value += operand.intValue();
}
/**
* Subtracts a value.
*
* @param operand
* the value to add
*
* @since Commons Lang 2.2
*/
public void subtract(int operand) {
this.value -= operand;
}
/**
* Subtracts a value.
*
* @param operand
* the value to add
* @throws NullPointerException
* if the object is null
*
* @since Commons Lang 2.2
*/
public void subtract(Number operand) {
this.value -= operand.intValue();
}
//-----------------------------------------------------------------------
// shortValue and bytValue rely on Number implementation
/**
* Returns the value of this MutableInt as a int.
*
* @return the numeric value represented by this object after conversion to type int.
*/
public int intValue() {
return value;
}
/**
* Returns the value of this MutableInt as a long.
*
* @return the numeric value represented by this object after conversion to type long.
*/
public long longValue() {
return value;
}
/**
* Returns the value of this MutableInt as a float.
*
* @return the numeric value represented by this object after conversion to type float.
*/
public float floatValue() {
return value;
}
/**
* Returns the value of this MutableInt as a double.
*
* @return the numeric value represented by this object after conversion to type double.
*/
public double doubleValue() {
return value;
}
//-----------------------------------------------------------------------
/**
* Gets this mutable as an instance of Integer.
*
* @return a Integer instance containing the value from this mutable
*/
public Integer toInteger() {
return new Integer(intValue());
}
//-----------------------------------------------------------------------
/**
* Compares this object to the specified object. The result is <code>true</code> if and only if the argument is
* not <code>null</code> and is an <code>MutableInt</code> object that contains the same <code>int</code> value
* as this object.
*
* @param obj
* the object to compare with.
* @return <code>true</code> if the objects are the same; <code>false</code> otherwise.
*/
public boolean equals(Object obj) {
if (obj instanceof MutableInt) {
return value == ((MutableInt) obj).intValue();
}
return false;
}
/**
* Returns a suitable hashcode for this mutable.
*
* @return a suitable hashcode
*/
public int hashCode() {
return value;
}
/**
* Compares this mutable to another in ascending order.
*
* @param obj
* the mutable to compare to
* @return negative if this is less, zero if equal, positive if greater
* @throws ClassCastException if the argument is not a MutableInt
*/
public int compareTo(Object obj) {
MutableInt other = (MutableInt) obj;
int anotherVal = other.value;
return value < anotherVal ? -1 : (value == anotherVal ? 0 : 1);
}
/**
* Returns the String value of this mutable.
*
* @return the mutable value as a string
*/
public String toString() {
return String.valueOf(value);
}
}
/*
* 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.
*/
/**
* Provides mutable access to a value.
* <p>
* <code>Mutable</code> is used as a generic interface to the implementations
* in this package.
* <p>
* A typical use case would be to enable a primitive or string to be passed to a
* method and allow that method to effectively change the value of the
* primitive/string. Another use case is to store a frequently changing
* primitive in a collection (for example a total in a map) without needing to
* create new Integer/Long wrapper objects.
*
* @author Matthew Hawthorne
* @since 2.1
* @version $Id: Mutable.java 618693 2008-02-05 16:33:29Z sebb $
*/
interface Mutable {
/**
* Gets the value of this mutable.
*
* @return the stored value
*/
Object getValue();
/**
* Sets the value of this mutable.
*
* @param value
* the value to store
* @throws NullPointerException
* if the object is null and null is invalid
* @throws ClassCastException
* if the type is invalid
*/
void setValue(Object value);
}
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