Example usage for java.util Comparator Comparator

Introduction

In this page you can find the example usage for java.util Comparator Comparator.

Prototype

Comparator

Source Link

Usage

From source file:Main.java

public static <T> Comparator<Collection<? extends T>> setComparator(
        final Comparator<? super T> elementComparator) {
    return new Comparator<Collection<? extends T>>() {
        @Override//from ww w  . j a v  a  2s  . com
        public int compare(Collection<? extends T> list1, Collection<? extends T> list2) {
            return compareAsSet(elementComparator, list1, list2);
        }
    };
}

From source file:Main.java

public static <K, V> List<Map.Entry<K, V>> sortMapByValue(HashMap<K, V> map, final int sort) {
    List<Map.Entry<K, V>> orderList = new ArrayList<Map.Entry<K, V>>(map.entrySet());
    Collections.sort(orderList, new Comparator<Map.Entry<K, V>>() {
        @Override//from   ww  w. j av a2  s .c  om
        @SuppressWarnings("unchecked")
        public int compare(Map.Entry<K, V> o1, Map.Entry<K, V> o2) {
            return (((Comparable<V>) o2.getValue()).compareTo(o1.getValue())) * sort;
        }
    });
    return orderList;
}

From source file:Main.java

public static <T, C> Collection<T> sortBy(Collection<T> collection, final Map<T, C> valuesMap) {
    List<T> ordered = new ArrayList<T>(collection);
    Comparator<T> compartor = new Comparator<T>() {

        @SuppressWarnings("unchecked")
        @Override//from  w w  w .ja  v a  2  s. co  m
        public int compare(T a, T b) {
            C aValue = valuesMap.get(a);
            C bValue = valuesMap.get(b);
            return ((Comparable<C>) aValue).compareTo(bValue);
        }
    };

    Collections.sort(ordered, compartor);

    return ordered;
}

From source file:Main.java

public static List<Map.Entry<String, Double>> sortMapByValue(Map<String, Double> map) {
    List<Map.Entry<String, Double>> list = new ArrayList<Map.Entry<String, Double>>(map.entrySet());
    Collections.sort(list, new Comparator<Map.Entry<String, Double>>() {
        @Override/*  w w  w.j a va  2s. c om*/
        public int compare(Entry<String, Double> o1, Entry<String, Double> o2) {
            double result = o2.getValue() - o1.getValue();
            if (result > 0)
                return -1;
            else if (result == 0)
                return 0;
            else
                return 1;
        }
    });
    return list;
}

From source file:Main.java

public static String[][] returnTable(Collection E) {
    if ((E == null) || E.isEmpty()) {
        System.out.println("The collection is empty!");
    }// w ww  .j ava 2  s .c o m

    Set<Field> collectionFields = new TreeSet<>(new Comparator<Field>() {
        @Override
        public int compare(Field o1, Field o2) {
            return o1.getName().compareTo(o2.getName());
        }
    });
    for (Object o : E) {
        Class c = o.getClass();
        createSetOfFields(collectionFields, c);
        while (c.getSuperclass() != null) {
            c = c.getSuperclass();
            createSetOfFields(collectionFields, c);
        }
    }
    String[][] exitText = new String[E.size() + 1][collectionFields.size() + 1];
    exitText[0][0] = String.format("%20s", "Class");
    int indexOfColumn = 0;
    for (Field f : collectionFields) {
        exitText[0][indexOfColumn + 1] = String.format("%20s", f.getName());
        indexOfColumn++;

    }
    int indexOfRow = 0;
    for (Object o : E) {
        indexOfColumn = 0;
        exitText[indexOfRow + 1][0] = String.format("%20s", o.getClass().getSimpleName());
        for (Field field : collectionFields) {
            try {
                field.setAccessible(true);
                if (field.get(o) instanceof Date) {
                    exitText[indexOfRow + 1][indexOfColumn + 1] = String.format("%20tD", field.get(o));
                } else {
                    String temp = String.valueOf(field.get(o));
                    exitText[indexOfRow + 1][indexOfColumn + 1] = String.format("%20s", temp);
                }
            } catch (Exception e) {
                exitText[indexOfRow + 1][indexOfColumn + 1] = String.format("%20s", "-");
            }
            indexOfColumn++;
        }
        indexOfRow++;
    }
    return exitText;
}

From source file:Main.java

public static <T extends Comparable> List<Entry<String, T>> sortMapAsc(Map<String, T> keywordMap) {
    List<Entry<String, T>> arrayList = new ArrayList<Entry<String, T>>(keywordMap.entrySet());
    Collections.sort(arrayList, new Comparator<Entry<String, T>>() {

        @Override// w w w.j  a v a2  s .  com
        public int compare(Entry<String, T> e1, Entry<String, T> e2) {
            return (e1.getValue()).compareTo(e2.getValue());
        }
    });
    return arrayList;
}

From source file:Main.java

public static <T extends Comparable> List<Entry<String, T>> sortMapDesc(Map<String, T> keywordMap) {
    List<Entry<String, T>> arrayList = new ArrayList<Entry<String, T>>(keywordMap.entrySet());
    Collections.sort(arrayList, new Comparator<Entry<String, T>>() {

        @Override/*from  w w  w  . j  a va2 s. co  m*/
        public int compare(Entry<String, T> e1, Entry<String, T> e2) {
            return (e2.getValue()).compareTo(e1.getValue());
        }
    });
    return arrayList;
}

From source file:Main.java

public static List<Message> getMessagesWithPage(Folder folder, int pageNum, int pageSize)
        throws MessagingException {
    Message[] messages = folder.getMessages();
    Arrays.sort(messages, new Comparator<Message>() {

        public int compare(Message o1, Message o2) {
            Message m1 = (Message) o1;/*w  w w.  j  a  va 2  s  .  co m*/
            Message m2 = (Message) o2;
            if (m1.getMessageNumber() > m2.getMessageNumber()) {
                return -1;
            }
            return 1;
        }

    });
    List<Message> list = Arrays.asList(messages);
    int start = (pageNum - 1) * pageSize;
    int end = pageNum * pageSize;
    return list.subList(start, end);
}

From source file:Main.java

public static <K, V> Map<K, V> sortMapByKey(Map<K, V> map, final Boolean asc) {
    List<Entry<K, V>> entries = new LinkedList<Entry<K, V>>(map.entrySet());
    Collections.sort(entries, new Comparator<Entry<K, V>>() {
        @SuppressWarnings("unchecked")
        public int compare(Entry<K, V> o1, Entry<K, V> o2) {
            if (asc) {
                return ((Comparable<K>) o1.getKey()).compareTo(o2.getKey());
            } else {
                return -((Comparable<K>) o1.getKey()).compareTo(o2.getKey());
            }//from w  w w  .jav a  2 s  . c  o  m
        }
    });

    Map<K, V> result = new LinkedHashMap<K, V>();
    for (Entry<K, V> entry : entries) {
        result.put(entry.getKey(), entry.getValue());
    }
    return result;
}

From source file:Main.java

public static <K, V extends Comparable<? super V>> Map<K, V> sortByValue(Map<K, V> map) {
    List<Map.Entry<K, V>> list = new LinkedList<>(map.entrySet());
    Collections.sort(list, new Comparator<Map.Entry<K, V>>() {
        public int compare(Map.Entry<K, V> o1, Map.Entry<K, V> o2) {
            return (o1.getValue()).compareTo(o2.getValue());
        }/*from  w  w w.java 2s .c  om*/
    });

    Map<K, V> result = new LinkedHashMap<>();
    for (Map.Entry<K, V> entry : list) {
        result.put(entry.getKey(), entry.getValue());
    }
    return result;
}