Converts a list of objects [a, 1, b, 2] into a map {a -> 1; b -> 2} - Java Collection Framework

Java examples for Collection Framework:Map

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Description

Converts a list of objects [a, 1, b, 2] into a map {a -> 1; b -> 2}

Demo Code

/*/*from   www.java  2 s.c o  m*/
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
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 *  software distributed under the License is distributed on an
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 *  KIND, either express or implied.  See the License for the
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 *  under the License.
 */
//package com.java2s;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

public class Main {
    /**
     * Converts a list of objects [a, 1, b, 2] into a map {a -> 1; b -> 2}
     */
    @SuppressWarnings("unchecked")
    public static <K, V> Map<K, V> asMap(Object... keyValPair) {
        Map<K, V> map = new HashMap<K, V>();

        if (keyValPair.length % 2 != 0) {
            throw new IllegalArgumentException(
                    "Keys and values must be pairs.");
        }

        for (int i = 0; i < keyValPair.length; i += 2) {
            map.put((K) keyValPair[i], (V) keyValPair[i + 1]);
        }

        return Collections.unmodifiableMap(map);
    }
}

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