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/* * Copyright 2014-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ package com.amazonaws.services.dynamodbv2.document; import java.util.Collection; import java.util.LinkedHashMap; import java.util.Map; import java.util.Set; import com.amazonaws.services.dynamodbv2.document.internal.InternalUtils; /** * Used to represent a primary key that has one or multiple key components. */ public class PrimaryKey { private final Map<String, KeyAttribute> components = new LinkedHashMap<String, KeyAttribute>(); public PrimaryKey() { } /** * Constructs with the specified key components. */ public PrimaryKey(KeyAttribute... components) { addComponents(components); } /** * Constructs with a hash key. */ public PrimaryKey(String hashKeyName, Object hashKeyValue) { addComponent(hashKeyName, hashKeyValue); } /** * Constructs with a hash key and a range key. */ public PrimaryKey(String hashKeyName, Object hashKeyValue, String rangeKeyName, Object rangeKeyValue) { if (hashKeyName.equals(rangeKeyName)) throw new IllegalArgumentException("hashKyeName must not be the same as the rangeKeyName"); addComponent(hashKeyName, hashKeyValue); addComponent(rangeKeyName, rangeKeyValue); } /** * Returns all the key components of this primary key. */ public Collection<KeyAttribute> getComponents() { return components.values(); } /** * Returns all the key component names of this primary key as a set. */ public Set<String> getComponentNameSet() { return components.keySet(); } /** * Returns true if this primary has the specified key attribute name; * false otherwise. */ public boolean hasComponent(String attrName) { return components.containsKey(attrName); } /** * Add one or multiple key components to this primary key. * * Note adding a key component with the same name as that of an existing * one would overwrite and become a single key component instead of two. */ public PrimaryKey addComponents(KeyAttribute... components) { if (components != null) { for (KeyAttribute ka : components) { InternalUtils.rejectNullInput(ka); this.components.put(ka.getName(), ka); } } return this; } /** * Add a key component to this primary key. * * Note adding a key component with the same name as that of an existing * one would overwrite and become a single key component instead of two. */ public PrimaryKey addComponent(String keyAttributeName, Object keyAttributeValue) { components.put(keyAttributeName, new KeyAttribute(keyAttributeName, keyAttributeValue)); return this; } @Override public String toString() { return String.valueOf(components); } @Override public int hashCode() { return components.hashCode(); } @Override public boolean equals(Object in) { if (in instanceof PrimaryKey) { PrimaryKey that = (PrimaryKey) in; return this.components.equals(that.components); } else { return false; } } }