collections

问题 This question already has answers here : Finding Key associated with max Value in a Java Map (16 answers) Closed 4 years ago . I have a HashMap of arbitrary objects, with Double values as the value: HashMap<MyObject, Double> myMap = new HashMap<>(); . I can get the maximum Double value in the HashMap using Collections.max(myMap.values()); but I need to get the corresponding key for that value. Is there an easy way to do this with the Collections API it or would I need an iterator? I've

问题 This question already has answers here : Finding Key associated with max Value in a Java Map (16 answers) Closed 4 years ago . I have a HashMap of arbitrary objects, with Double values as the value: HashMap<MyObject, Double> myMap = new HashMap<>(); . I can get the maximum Double value in the HashMap using Collections.max(myMap.values()); but I need to get the corresponding key for that value. Is there an easy way to do this with the Collections API it or would I need an iterator? I've

问题 This question already has answers here : Finding Key associated with max Value in a Java Map (16 answers) Closed 4 years ago . I have a HashMap of arbitrary objects, with Double values as the value: HashMap<MyObject, Double> myMap = new HashMap<>(); . I can get the maximum Double value in the HashMap using Collections.max(myMap.values()); but I need to get the corresponding key for that value. Is there an easy way to do this with the Collections API it or would I need an iterator? I've

问题 I have Base date Ranges and Test Date Range. I need to get GAP between base and test meaning Missing Date Ranges that are in Base but not in Test. what would be the best way to do this? Base Date Ranges 1/1/2012 1/10/2012 1/11/2012 1/25/2012 Test Date Ranges 1/2/2012 1/7/2012 1/8/2012 1/9/2012 1/15/2012 1/30/2012 Output: Missing Date Ranges that are in Base but not in Test 1/1/2012 1/2/2012 1/7/2012 1/8/2012 1/9/2012 1/10/2012 1/11/2012 1/15/2012 Tried this so far static void Main(string[]

问题 I have Base date Ranges and Test Date Range. I need to get GAP between base and test meaning Missing Date Ranges that are in Base but not in Test. what would be the best way to do this? Base Date Ranges 1/1/2012 1/10/2012 1/11/2012 1/25/2012 Test Date Ranges 1/2/2012 1/7/2012 1/8/2012 1/9/2012 1/15/2012 1/30/2012 Output: Missing Date Ranges that are in Base but not in Test 1/1/2012 1/2/2012 1/7/2012 1/8/2012 1/9/2012 1/10/2012 1/11/2012 1/15/2012 Tried this so far static void Main(string[]

问题 I'm looking for a compact syntax for instantiating a collection and adding a few items to it. I currently use this syntax: Collection<String> collection = new ArrayList<String>(Arrays.asList(new String[] { "1", "2", "3" })); I seem to recall that there's a more compact way of doing this that uses an anonymous subclass of ArrayList , then adds the items in the subclass' constructor. However, I can't seem to remember the exact syntax. 回答1: http://blog.firdau.si/2010/07/01/java-tips-initializing

问题 I'm looking for a compact syntax for instantiating a collection and adding a few items to it. I currently use this syntax: Collection<String> collection = new ArrayList<String>(Arrays.asList(new String[] { "1", "2", "3" })); I seem to recall that there's a more compact way of doing this that uses an anonymous subclass of ArrayList , then adds the items in the subclass' constructor. However, I can't seem to remember the exact syntax. 回答1: http://blog.firdau.si/2010/07/01/java-tips-initializing

问题 I'm looking for a compact syntax for instantiating a collection and adding a few items to it. I currently use this syntax: Collection<String> collection = new ArrayList<String>(Arrays.asList(new String[] { "1", "2", "3" })); I seem to recall that there's a more compact way of doing this that uses an anonymous subclass of ArrayList , then adds the items in the subclass' constructor. However, I can't seem to remember the exact syntax. 回答1: http://blog.firdau.si/2010/07/01/java-tips-initializing

问题 I have list of objects. Assuming the structure of object is as follows. class Test { Int id; String y; } A 'testList' has four instances of Test class which are t1, t2, t3, t4. Requirement is the if multiple instances has the same value for field 'y', they all should be removed from the list. Duplicate values is considered as error scenario and those instances are dealt separately. For instance in the above case if instance t3 and t4 has same value for 'y' field the processed list should only

问题 I have list of objects. Assuming the structure of object is as follows. class Test { Int id; String y; } A 'testList' has four instances of Test class which are t1, t2, t3, t4. Requirement is the if multiple instances has the same value for field 'y', they all should be removed from the list. Duplicate values is considered as error scenario and those instances are dealt separately. For instance in the above case if instance t3 and t4 has same value for 'y' field the processed list should only