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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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// Adapted from bug report 5018354 |
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import java.util.*; |
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|
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public class LastKeyOfSubMap { |
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private static final Comparator NULL_AT_END = new Comparator() { |
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/** |
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* Allows for nulls. Null is greater than anything non-null. |
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*/ |
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public int compare(Object pObj1, Object pObj2) { |
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if (pObj1 == null && pObj2 == null) return 0; |
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if (pObj1 == null && pObj2 != null) return 1; |
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if (pObj1 != null && pObj2 == null) return -1; |
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return ((Comparable) pObj1).compareTo(pObj2); |
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} |
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}; |
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|
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public static void main(String[] pArgs) { |
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SortedMap m1 = new TreeMap(NULL_AT_END); |
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m1.put("a", "a"); |
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m1.put("b", "b"); |
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m1.put("c", "c"); |
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m1.put(null, "d"); |
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|
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SortedMap m2 = new TreeMap(m1); |
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|
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System.out.println(m1.lastKey()); |
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System.out.println(m1.get(m1.lastKey())); |
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Object m1lk = m1.remove(m1.lastKey()); |
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if (m1lk == null) |
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throw new Error("bad remove of last key"); |
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|
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m2 = m2.tailMap("b"); |
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|
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System.out.println(m2.lastKey()); |
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System.out.println(m2.get(m2.lastKey())); |
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Object m2lk = m2.remove(m2.lastKey()); |
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if (m2lk == null) |
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throw new Error("bad remove of last key"); |
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} |
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} |
