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*/ |
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package java.util; |
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import java.util.*; // for javadoc (till 6280605 is fixed) |
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import java.util.Map.Entry; |
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/** |
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// Comparison and hashing |
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|
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/** |
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* {@inheritDoc} |
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* Compares the specified object with this map for equality. Returns |
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* <tt>true</tt> if the given object is also a map and the two maps |
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* represent the same mappings. More formally, two maps <tt>m1</tt> and |
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* <tt>m2</tt> represent the same mappings if |
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* <tt>m1.entrySet().equals(m2.entrySet())</tt>. This ensures that the |
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* <tt>equals</tt> method works properly across different implementations |
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* of the <tt>Map</tt> interface. |
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* |
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* <p>This implementation first checks if the specified object is this map; |
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* if so it returns <tt>true</tt>. Then, it checks if the specified |
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* contains each mapping that this map contains. If the specified map |
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* fails to contain such a mapping, <tt>false</tt> is returned. If the |
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* iteration completes, <tt>true</tt> is returned. |
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* |
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* @param o object to be compared for equality with this map |
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* @return <tt>true</tt> if the specified object is equal to this map |
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*/ |
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public boolean equals(Object o) { |
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if (o == this) |
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|
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if (!(o instanceof Map)) |
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return false; |
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Map<K,V> t = (Map<K,V>) o; |
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if (t.size() != size()) |
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Map<K,V> m = (Map<K,V>) o; |
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if (m.size() != size()) |
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return false; |
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|
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try { |
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K key = e.getKey(); |
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V value = e.getValue(); |
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if (value == null) { |
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if (!(t.get(key)==null && t.containsKey(key))) |
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if (!(m.get(key)==null && m.containsKey(key))) |
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return false; |
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} else { |
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if (!value.equals(t.get(key))) |
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if (!value.equals(m.get(key))) |
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return false; |
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} |
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} |
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} |
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|
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/** |
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< |
* {@inheritDoc} |
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* Returns the hash code value for this map. The hash code of a map is |
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* defined to be the sum of the hash codes of each entry in the map's |
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* <tt>entrySet()</tt> view. This ensures that <tt>m1.equals(m2)</tt> |
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* implies that <tt>m1.hashCode()==m2.hashCode()</tt> for any two maps |
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* <tt>m1</tt> and <tt>m2</tt>, as required by the general contract of |
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* {@link Object#hashCode}. |
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* |
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* <p>This implementation iterates over <tt>entrySet()</tt>, calling |
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* <tt>hashCode()</tt> on each element (entry) in the set, and |
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* adding up the results. |
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* {@link Map.Entry#hashCode hashCode()} on each element (entry) in the |
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* set, and adding up the results. |
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* |
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* @return the hash code value for this map |
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* @see Map.Entry#hashCode() |
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* @see Object#hashCode() |
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* @see Object#equals(Object) |
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* @see Set#equals(Object) |
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*/ |
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* appended. Finally a right brace is appended. A string is obtained |
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* from the stringbuffer, and returned. |
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* |
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* @return a String representation of this map. |
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* @return a String representation of this map |
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*/ |
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public String toString() { |
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StringBuffer buf = new StringBuffer(); |
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buf.append("{"); |
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StringBuilder sb = new StringBuilder(); |
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sb.append("{"); |
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|
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Iterator<Entry<K,V>> i = entrySet().iterator(); |
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boolean hasNext = i.hasNext(); |
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K key = e.getKey(); |
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V value = e.getValue(); |
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if (key == this) |
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buf.append("(this Map)"); |
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sb.append("(this Map)"); |
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else |
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buf.append(key); |
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buf.append("="); |
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sb.append(key); |
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sb.append("="); |
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if (value == this) |
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< |
buf.append("(this Map)"); |
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> |
sb.append("(this Map)"); |
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else |
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< |
buf.append(value); |
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> |
sb.append(value); |
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hasNext = i.hasNext(); |
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if (hasNext) |
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buf.append(", "); |
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sb.append(", "); |
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} |
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|
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< |
buf.append("}"); |
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< |
return buf.toString(); |
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> |
sb.append("}"); |
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return sb.toString(); |
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} |
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|
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/** |
549 |
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* implementations. For example, it may be convenient to return |
550 |
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* arrays of <tt>SimpleEntry</tt> instances in method |
551 |
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* <tt>Map.entrySet().toArray</tt> |
552 |
+ |
* |
553 |
+ |
* @since 1.6 |
554 |
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*/ |
555 |
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public static class SimpleEntry<K,V> implements Entry<K,V> { |
556 |
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private final K key; |
572 |
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* Creates an entry representing the same mapping as the |
573 |
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* specified entry. |
574 |
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* |
575 |
< |
* @param entry the entry to copy. |
575 |
> |
* @param entry the entry to copy |
576 |
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*/ |
577 |
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public SimpleEntry(Entry<? extends K, ? extends V> entry) { |
578 |
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this.key = entry.getKey(); |
641 |
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* does not support method <tt>setValue</tt>. This class may be |
642 |
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* convenient in methods that return thread-safe snapshots of |
643 |
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* key-value mappings. |
644 |
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* |
645 |
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* @since 1.6 |
646 |
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*/ |
647 |
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public static class SimpleImmutableEntry<K,V> implements Entry<K,V> { |
648 |
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private final K key; |