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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 com.amazonaws.services.dynamodbv2.document.internal.InternalUtils; import com.amazonaws.services.dynamodbv2.model.ComparisonOperator; /** * Represents a condition to be compared with an attribute value. * <p> * Typical usages: * <blockquote> * <code>new Expected("strAttr").eq("attrValue");</code> * <p> * <code>new Expected("intAttr").gt(42);</code> * <p> * ... * </blockquote> * <p> * See * http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/ * API_ExpectedAttributeValue.html. */ public class Expected { private final String attribute; private ComparisonOperator op; private Object[] values; public Expected(String attrName) { InternalUtils.checkInvalidAttrName(attrName); this.attribute = attrName; } /** Returns the attribute. */ public String getAttribute() { return attribute; } public ComparisonOperator getComparisonOperator() { return op; } public Object[] getValues() { return values == null ? null : values.clone(); } private Expected _withValues(Object... values) { this.values = values.clone(); return this; } private Expected _withComparisonOperator(ComparisonOperator op) { this.op = op; return this; } /** * Creates and returns a condition of the range key being equal to the given * value. */ public Expected eq(Object val) { return _withComparisonOperator(ComparisonOperator.EQ)._withValues(val); } public Expected ne(Object val) { return _withComparisonOperator(ComparisonOperator.NE)._withValues(val); } /** * Expects the attribute be an existing attribute. */ public Expected exists() { return _withComparisonOperator(ComparisonOperator.NOT_NULL); } /** * Expects the attribute be non-existing. */ public Expected notExist() { return _withComparisonOperator(ComparisonOperator.NULL); } public Expected contains(Object val) { return _withComparisonOperator(ComparisonOperator.CONTAINS)._withValues(val); } public Expected notContains(Object val) { return _withComparisonOperator(ComparisonOperator.NOT_CONTAINS)._withValues(val); } /** * Creates and returns a condition of the range key with a value that begins * with the given value. */ public Expected beginsWith(String val) { return _withComparisonOperator(ComparisonOperator.BEGINS_WITH)._withValues(val); } public Expected in(Object... values) { if (values == null || values.length == 0) { throw new IllegalArgumentException("values must not be null or empty."); } return _withComparisonOperator(ComparisonOperator.IN)._withValues(values); } /** * Creates and returns a condition of the range key that has a value between * the given values. */ public Expected between(Object low, Object hi) { return _withComparisonOperator(ComparisonOperator.BETWEEN)._withValues(low, hi); } /** * Creates and returns a condition of the range key being greater than or * equal to the given value. */ public Expected ge(Object val) { return _withComparisonOperator(ComparisonOperator.GE)._withValues(val); } /** * Creates and returns a condition of the range key being greater than the * given value. */ public Expected gt(Object val) { return _withComparisonOperator(ComparisonOperator.GT)._withValues(val); } /** * Creates and returns a condition of the range key being less than or equal * to the given value. */ public Expected le(Object val) { return _withComparisonOperator(ComparisonOperator.LE)._withValues(val); } /** * Creates and returns a condition of the range key being less than the * given value. */ public Expected lt(Object val) { return _withComparisonOperator(ComparisonOperator.LT)._withValues(val); } }