comparator

问题 The below code is in Class String in java. I don't understand why the characters from two different strings are compared twice . at first by doing upper case and if that fails by doing lower case. My Question here is, is it required? If yes, why? public static final Comparator<String> CASE_INSENSITIVE_ORDER = new CaseInsensitiveComparator(); private static class CaseInsensitiveComparator implements Comparator<String>, java.io.Serializable { // use serialVersionUID from JDK 1.2.2 for

问题 The below code is in Class String in java. I don't understand why the characters from two different strings are compared twice . at first by doing upper case and if that fails by doing lower case. My Question here is, is it required? If yes, why? public static final Comparator<String> CASE_INSENSITIVE_ORDER = new CaseInsensitiveComparator(); private static class CaseInsensitiveComparator implements Comparator<String>, java.io.Serializable { // use serialVersionUID from JDK 1.2.2 for

问题 I have implemented a chat function in my app and it's working fine, only problem is that now I want the chats to be ordered by timestamp , so that the newest ones come first and the oldest come last. I have tried doing so using Comparator, but for some reason it's not working and I am not sure how to fix it. Below you have my MessageActivity where I save the chats to the Firebase, and my ChatFragment that contains the ArrayList for the chats. The chats are appearing there, but I can't get

问题 I have implemented a chat function in my app and it's working fine, only problem is that now I want the chats to be ordered by timestamp , so that the newest ones come first and the oldest come last. I have tried doing so using Comparator, but for some reason it's not working and I am not sure how to fix it. Below you have my MessageActivity where I save the chats to the Firebase, and my ChatFragment that contains the ArrayList for the chats. The chats are appearing there, but I can't get

问题 I want to implement my custom Comparator to sort a map of keys in this particular way: 1 2 3 4 4a 4b 5 6 11 12 12a ... And I dont know how can do it exactly. I have impelemented this only for numeric values: aaa = new TreeMap<String, ArrayList<ETrack>>( new Comparator<String>() { @Override public int compare(String s1, String s2) { return Integer.valueOf(s1).compareTo(Integer.valueOf(s2)); } }); But this is not obiouslly the complete solution. Any idea? 回答1: One approach is to map the strings

问题 I want to implement my custom Comparator to sort a map of keys in this particular way: 1 2 3 4 4a 4b 5 6 11 12 12a ... And I dont know how can do it exactly. I have impelemented this only for numeric values: aaa = new TreeMap<String, ArrayList<ETrack>>( new Comparator<String>() { @Override public int compare(String s1, String s2) { return Integer.valueOf(s1).compareTo(Integer.valueOf(s2)); } }); But this is not obiouslly the complete solution. Any idea? 回答1: One approach is to map the strings

来源： https://stackoverflow.com/questions/33479938/priority-queue-with-custom-comparator-segmentation-fault-when-pushing-second-tim

来源： https://stackoverflow.com/questions/33479938/priority-queue-with-custom-comparator-segmentation-fault-when-pushing-second-tim

来源： https://stackoverflow.com/questions/24565278/java-util-comparator-naturalorder-takes-a-t-extends-comparable-super-t-and

来源： https://stackoverflow.com/questions/24565278/java-util-comparator-naturalorder-takes-a-t-extends-comparable-super-t-and