org.apache.commons.collections.DefaultMapEntry Maven / Gradle / Ivy
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* "This product includes software developed by the
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* DefaultMapEntry with a null key
* and null value.
*/
public DefaultMapEntry() {
super();
}
/**
* Constructs a new DefaultMapEntry with the given
* key and given value.
*
* @param entry the entry to copy, must not be null
* @throws NullPointerException if the entry is null
*/
public DefaultMapEntry(Map.Entry entry) {
super();
this.key = entry.getKey();
this.value = entry.getValue();
}
/**
* Constructs a new DefaultMapEntry with the given
* key and given value.
*
* @param key the key for the entry, may be null
* @param value the value for the entry, may be null
*/
public DefaultMapEntry(Object key, Object value) {
super();
this.key = key;
this.value = value;
}
// Map.Entry interface
//-------------------------------------------------------------------------
/**
* Gets the key from the Map Entry.
*
* @return the key
*/
public Object getKey() {
return key;
}
/**
* Sets the key stored in this Map Entry.
*
* This Map Entry is not connected to a Map, so only the local data is changed.
*
* @param key the new key
*/
public void setKey(Object key) {
this.key = key;
}
/**
* Gets the value from the Map Entry.
*
* @return the value
*/
public Object getValue() {
return value;
}
/**
* Sets the value stored in this Map Entry.
*
* This Map Entry is not connected to a Map, so only the local data is changed.
*
* @param value the new value
* @return the previous value
*/
public Object setValue(Object value) {
Object answer = this.value;
this.value = value;
return answer;
}
// Basics
//-----------------------------------------------------------------------
/**
* Compares this Map Entry with another Map Entry.
*
* Implemented per API documentation of {@link java.util.Map.Entry#equals(Object)}
*
* @param obj the object to compare to
* @return true if equal key and value
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (obj instanceof Map.Entry == false) {
return false;
}
Map.Entry other = (Map.Entry) obj;
return
(getKey() == null ? other.getKey() == null : getKey().equals(other.getKey())) &&
(getValue() == null ? other.getValue() == null : getValue().equals(other.getValue()));
}
/**
* Gets a hashCode compatible with the equals method.
*
* Implemented per API documentation of {@link java.util.Map.Entry#hashCode()}
*
* @return a suitable hash code
*/
public int hashCode() {
return (getKey() == null ? 0 : getKey().hashCode()) ^
(getValue() == null ? 0 : getValue().hashCode());
}
/**
* Written to match the output of the Map.Entry's used in
* a {@link java.util.HashMap}.
* @since 3.0
*/
public String toString() {
return ""+getKey()+"="+getValue();
}
}