Package de.gsi.dataset.utils

Class Cache<K,​V>

  • Type Parameters:
    K - search key
    V - cached value
    All Implemented Interfaces:
    java.util.Map<K,​V>
    public class Cache<K,​V>
extends java.lang.Object
implements java.util.Map<K,​V>
    A simple map based cache with timeOut and limit usage example: 
      
     public class Demo {
         private Cache<String, Integer> cache;

         public Demo() {
             cache = final Cache<String, Integer> cache = Cache.<String, Integer>builder().withLimit(10)
                  .withTimeout(100, TimeUnit.MILLISECONDS).build();
             // alternatively:
             // cache = new Cache(100, TimeUnit.MILLISECONDS, 10);

             String name1 = "Han Solo";

             cache.put(name1, 10);

             System.out.println(name1 + " is cached: " + isCached(name1));

             // Wait 1 second
             try {
                 Thread.sleep(1000);
             } catch (InterruptedException e) {
                 e.printStackTrace();
             }

             System.out.println(name1 + " is cached: " + isCached(name1));

             // Wait another second
             try {
                 Thread.sleep(1000);
             } catch (InterruptedException e) {
                 e.printStackTrace();
             }

             System.out.println(name1 + " is cached: " + isCached(name1));
         }

         private boolean isCached(final String KEY) {
             return cache.get(KEY).isPresent();
         }

         public static void main(String[] args) {
             new Demo();
         }
     }
    Original code courtesy from: https://github.com/HanSolo/cache
    Author:
    Gerrit Grunwald (aka. HanSolo, original concept), rstein

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  Cache.CacheBuilder<K2,​V2>  

      • Nested classes/interfaces inherited from interface java.util.Map

        java.util.Map.Entry<K extends java.lang.Object,​V extends java.lang.Object>

    • Constructor Summary

      Constructors 
      Constructor Description
      Cache​(int limit)  
      Cache​(long timeOut, java.util.concurrent.TimeUnit timeUnit)  
      Cache​(long timeOut, java.util.concurrent.TimeUnit timeUnit, int limit)  

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static <K3,​V3>
      Cache.CacheBuilder<K3,​V3>      		 builder()  
      protected void checkSize()  
      protected void checkSize​(int nNewElements)  
      protected void checkTime()  
      protected static int clamp​(int min, int max, int value)  
      protected static long clamp​(long min, long max, long value)  
      void clear()  
      boolean containsKey​(java.lang.Object key)  
      boolean containsValue​(java.lang.Object value)  
      protected static java.time.temporal.ChronoUnit convertToChronoUnit​(java.util.concurrent.TimeUnit timeUnit)  
      java.util.Set<java.util.Map.Entry<K,​V>> entrySet()  
      V get​(java.lang.Object key)  
      V getIfPresent​(K key)  
      long getLimit()  
      java.util.Optional<V> getOptional​(K key)  
      int getSize()  
      long getTimeout()  
      java.util.concurrent.TimeUnit getTimeUnit()  
      boolean isEmpty()  
      java.util.Set<K> keySet()  
      V put​(K key, V value)  
      void putAll​(java.util.Map<? extends K,​? extends V> m)  
      V putIfAbsent​(K key, V value)  
      V remove​(java.lang.Object key)  
      int size()  
      java.util.Collection<V> values()  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

      • Methods inherited from interface java.util.Map

        compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, remove, replace, replace, replaceAll

    • Constructor Detail

      • Cache

        public Cache​(int limit)

      • Cache

        public Cache​(long timeOut,
             java.util.concurrent.TimeUnit timeUnit)

      • Cache

        public Cache​(long timeOut,
             java.util.concurrent.TimeUnit timeUnit,
             int limit)

    • Method Detail

      • clear

        public void clear()
        Specified by:
        clear in interface java.util.Map<K,​V>

      • containsKey

        public boolean containsKey​(java.lang.Object key)
        Specified by:
        containsKey in interface java.util.Map<K,​V>

      • containsValue

        public boolean containsValue​(java.lang.Object value)
        Specified by:
        containsValue in interface java.util.Map<K,​V>

      • entrySet

        public java.util.Set<java.util.Map.Entry<K,​V>> entrySet()
        Specified by:
        entrySet in interface java.util.Map<K,​V>

      • get

        public V get​(java.lang.Object key)
        Specified by:
        get in interface java.util.Map<K,​V>

      • getIfPresent

        public V getIfPresent​(K key)

      • getLimit

        public long getLimit()

      • getOptional

        public java.util.Optional<V> getOptional​(K key)

      • getSize

        public int getSize()

      • getTimeout

        public long getTimeout()

      • getTimeUnit

        public java.util.concurrent.TimeUnit getTimeUnit()

      • isEmpty

        public boolean isEmpty()
        Specified by:
        isEmpty in interface java.util.Map<K,​V>

      • keySet

        public java.util.Set<K> keySet()
        Specified by:
        keySet in interface java.util.Map<K,​V>

      • put

        public V put​(K key,
             V value)
        Specified by:
        put in interface java.util.Map<K,​V>

      • putIfAbsent

        public V putIfAbsent​(K key,
                     V value)
        Specified by:
        putIfAbsent in interface java.util.Map<K,​V>

      • putAll

        public void putAll​(java.util.Map<? extends K,​? extends V> m)
        Specified by:
        putAll in interface java.util.Map<K,​V>

      • remove

        public V remove​(java.lang.Object key)
        Specified by:
        remove in interface java.util.Map<K,​V>

      • size

        public int size()
        Specified by:
        size in interface java.util.Map<K,​V>

      • values

        public java.util.Collection<V> values()
        Specified by:
        values in interface java.util.Map<K,​V>

      • checkSize

        protected void checkSize()

      • checkSize

        protected void checkSize​(int nNewElements)

      • checkTime

        protected void checkTime()

      • clamp

        protected static int clamp​(int min,
                           int max,
                           int value)

      • clamp

        protected static long clamp​(long min,
                            long max,
                            long value)

      • convertToChronoUnit

        protected static java.time.temporal.ChronoUnit convertToChronoUnit​(java.util.concurrent.TimeUnit timeUnit)