org.rajivprab.cava.Mapc Maven / Gradle / Ivy

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package org.rajivprab.cava;

import com.google.common.cache.Cache;
import com.google.common.collect.Maps;
import com.google.common.util.concurrent.UncheckedExecutionException;

import java.util.HashMap;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;

/**
 * Map related utility functions.
 * 
 * The newHashMap functionality, with Object varargs, has been removed due to numerous type-safety issues uncovered.
 * To construct hash-maps with size greater than 5, recommend not using any such initializer below.
 * 
 * Created by rprabhakar on 12/15/15.
 */
public class Mapc {
    // Calls cache.get with exception handling that throws the cause itself, and not the wrapping ExecutionException
    public static  V cacheGet(Cache cache, K key, Callable callable) {
        try {
            return cache.get(key, callable);
        } catch (ExecutionException | UncheckedExecutionException e) {
            if (e.getCause() instanceof RuntimeException) {
                throw (RuntimeException) e.getCause();
            } else {
                throw new CheckedExceptionWrapper(e.getCause());
            }
        }
    }

    public static  HashMap newHashMap(K key1, V value1) {
        HashMap map = Maps.newHashMap();
        map.put(key1, value1);
        return map;
    }

    public static  HashMap newHashMap(K key1, V value1,
                                                  K key2, V value2) {
        HashMap map = newHashMap(key1, value1);
        map.put(key2, value2);
        return map;
    }

    public static  HashMap newHashMap(K key1, V value1,
                                                  K key2, V value2,
                                                  K key3, V value3) {
        HashMap map = newHashMap(key1, value1, key2, value2);
        map.put(key3, value3);
        return map;
    }

    public static  HashMap newHashMap(K key1, V value1,
                                                  K key2, V value2,
                                                  K key3, V value3,
                                                  K key4, V value4) {
        HashMap map = newHashMap(key1, value1, key2, value2, key3, value3);
        map.put(key4, value4);
        return map;
    }

    public static  HashMap newHashMap(K key1, V value1,
                                                  K key2, V value2,
                                                  K key3, V value3,
                                                  K key4, V value4,
                                                  K key5, V value5) {
        HashMap map = newHashMap(key1, value1, key2, value2, key3, value3, key4, value4);
        map.put(key5, value5);
        return map;
    }
}