Package org.apache.camel.util

Class CollectionHelper

java.lang.Object
org.apache.camel.util.CollectionHelper
public final class CollectionHelper extends Object
A number of helper methods for working with collections

  • Method Details

    • size

      public static Integer size(Object value)
      Returns the size of the collection if it can be determined to be a collection
      Parameters:
      value - the collection
      Returns:
      the size, or null if not a collection

    • appendValue

      public static void appendValue(Map<String,Object> map, String key, Object value)
      Sets the value of the entry in the map for the given key, though if the map already contains a value for the given key then the value is appended to a list of values.
      Parameters:
      map - the map to add the entry to
      key - the key in the map
      value - the value to put in the map

    • createSetContaining

      @SafeVarargs public static <T> Set<T> createSetContaining(T... contents)

    • collectionAsCommaDelimitedString

      public static String collectionAsCommaDelimitedString(Collection<?> col)

    • flattenKeysInMap

      public static Map<String,Object> flattenKeysInMap(Map<String,Object> map, String separator)
      Traverses the given map recursively and flattern the keys by combining them with the optional separator.
      Parameters:
      map - the map
      separator - optional separator to use in key name, for example a hyphen or dot.
      Returns:
      the map with flattern keys

    • unmodifiableMap

      public static <K, V> Map<K,V> unmodifiableMap(Map<K,V> map)
      Build an unmodifiable map on top of a given map. Note tha thew given map is copied if not null.
      Parameters:
      map - a map
      Returns:
      an unmodifiable map.

    • mapOf

      public static <K, V> Map<K,V> mapOf(Supplier<Map<K,V>> creator, K key, V value, Object... keyVals)
      Build a map from varargs.

    • immutableMapOf

      public static <K, V> Map<K,V> immutableMapOf(Supplier<Map<K,V>> creator, K key, V value, Object... keyVals)
      Build an immutable map from varargs.

    • mapOf

      public static <K, V> Map<K,V> mapOf(K key, V value, Object... keyVals)
      Build a map from varargs.

    • immutableMapOf

      public static <K, V> Map<K,V> immutableMapOf(K key, V value, Object... keyVals)
      Build an immutable map from varargs.

    • propertiesOf

      public static Properties propertiesOf(String key, String value, String... keyVals)
      Build a Properties from varargs.

    • mergeMaps

      @SafeVarargs public static <K, V> Map<K,V> mergeMaps(Map<K,V> map, Map<K,V>... maps)
      Build a new map that is the result of merging the given list of maps.