Java tutorial
/* * 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.model; import java.io.Serializable; import javax.annotation.Generated; import com.amazonaws.protocol.StructuredPojo; import com.amazonaws.protocol.ProtocolMarshaller; /** * <p> * Represents a set of primary keys and, for each key, the attributes to retrieve from the table. * </p> * <p> * For each primary key, you must provide <i>all</i> of the key attributes. For example, with a simple primary key, you * only need to provide the partition key. For a composite primary key, you must provide <i>both</i> the partition key * and the sort key. * </p> * * @see <a href="http://docs.aws.amazon.com/goto/WebAPI/dynamodb-2012-08-10/KeysAndAttributes" target="_top">AWS API * Documentation</a> */ @Generated("com.amazonaws:aws-java-sdk-code-generator") public class KeysAndAttributes implements Serializable, Cloneable, StructuredPojo { /** * <p> * The primary key attribute values that define the items and the attributes associated with the items. * </p> */ private java.util.List<java.util.Map<String, AttributeValue>> keys; /** * <p> * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html">Legacy * Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> */ private java.util.List<String> attributesToGet; /** * <p> * The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is used; * otherwise, an eventually consistent read is used. * </p> */ private Boolean consistentRead; /** * <p> * A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, * sets, or elements of a JSON document. The attributes in the <code>ProjectionExpression</code> must be separated * by commas. * </p> * <p> * If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are * not found, they will not appear in the result. * </p> * <p> * For more information, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> */ private String projectionExpression; /** * <p> * One or more substitution tokens for attribute names in an expression. The following are some use cases for using * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * To access an attribute whose name conflicts with a DynamoDB reserved word. * </p> * </li> * <li> * <p> * To create a placeholder for repeating occurrences of an attribute name in an expression. * </p> * </li> * <li> * <p> * To prevent special characters in an attribute name from being misinterpreted in an expression. * </p> * </li> * </ul> * <p> * Use the <b>#</b> character in an expression to dereference an attribute name. For example, consider the following * attribute name: * </p> * <ul> * <li> * <p> * <code>Percentile</code> * </p> * </li> * </ul> * <p> * The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For * the complete list of reserved words, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html">Reserved Words</a> in * the <i>Amazon DynamoDB Developer Guide</i>). To work around this, you could specify the following for * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * <code>{"#P":"Percentile"}</code> * </p> * </li> * </ul> * <p> * You could then use this substitution in an expression, as in this example: * </p> * <ul> * <li> * <p> * <code>#P = :val</code> * </p> * </li> * </ul> * <note> * <p> * Tokens that begin with the <b>:</b> character are <i>expression attribute values</i>, which are placeholders for * the actual value at runtime. * </p> * </note> * <p> * For more information on expression attribute names, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> */ private java.util.Map<String, String> expressionAttributeNames; /** * <p> * The primary key attribute values that define the items and the attributes associated with the items. * </p> * * @return The primary key attribute values that define the items and the attributes associated with the items. */ public java.util.List<java.util.Map<String, AttributeValue>> getKeys() { return keys; } /** * <p> * The primary key attribute values that define the items and the attributes associated with the items. * </p> * * @param keys * The primary key attribute values that define the items and the attributes associated with the items. */ public void setKeys(java.util.Collection<java.util.Map<String, AttributeValue>> keys) { if (keys == null) { this.keys = null; return; } this.keys = new java.util.ArrayList<java.util.Map<String, AttributeValue>>(keys); } /** * <p> * The primary key attribute values that define the items and the attributes associated with the items. * </p> * <p> * <b>NOTE:</b> This method appends the values to the existing list (if any). Use * {@link #setKeys(java.util.Collection)} or {@link #withKeys(java.util.Collection)} if you want to override the * existing values. * </p> * * @param keys * The primary key attribute values that define the items and the attributes associated with the items. * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes withKeys(java.util.Map<String, AttributeValue>... keys) { if (this.keys == null) { setKeys(new java.util.ArrayList<java.util.Map<String, AttributeValue>>(keys.length)); } for (java.util.Map<String, AttributeValue> ele : keys) { this.keys.add(ele); } return this; } /** * <p> * The primary key attribute values that define the items and the attributes associated with the items. * </p> * * @param keys * The primary key attribute values that define the items and the attributes associated with the items. * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes withKeys(java.util.Collection<java.util.Map<String, AttributeValue>> keys) { setKeys(keys); return this; } /** * <p> * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html">Legacy * Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @return This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html"> * Legacy Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. */ public java.util.List<String> getAttributesToGet() { return attributesToGet; } /** * <p> * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html">Legacy * Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @param attributesToGet * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html"> * Legacy Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. */ public void setAttributesToGet(java.util.Collection<String> attributesToGet) { if (attributesToGet == null) { this.attributesToGet = null; return; } this.attributesToGet = new java.util.ArrayList<String>(attributesToGet); } /** * <p> * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html">Legacy * Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * <p> * <b>NOTE:</b> This method appends the values to the existing list (if any). Use * {@link #setAttributesToGet(java.util.Collection)} or {@link #withAttributesToGet(java.util.Collection)} if you * want to override the existing values. * </p> * * @param attributesToGet * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html"> * Legacy Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes withAttributesToGet(String... attributesToGet) { if (this.attributesToGet == null) { setAttributesToGet(new java.util.ArrayList<String>(attributesToGet.length)); } for (String ele : attributesToGet) { this.attributesToGet.add(ele); } return this; } /** * <p> * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html">Legacy * Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @param attributesToGet * This is a legacy parameter. Use <code>ProjectionExpression</code> instead. For more information, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html"> * Legacy Conditional Parameters</a> in the <i>Amazon DynamoDB Developer Guide</i>. * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes withAttributesToGet(java.util.Collection<String> attributesToGet) { setAttributesToGet(attributesToGet); return this; } /** * <p> * The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is used; * otherwise, an eventually consistent read is used. * </p> * * @param consistentRead * The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is used; * otherwise, an eventually consistent read is used. */ public void setConsistentRead(Boolean consistentRead) { this.consistentRead = consistentRead; } /** * <p> * The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is used; * otherwise, an eventually consistent read is used. * </p> * * @return The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is * used; otherwise, an eventually consistent read is used. */ public Boolean getConsistentRead() { return this.consistentRead; } /** * <p> * The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is used; * otherwise, an eventually consistent read is used. * </p> * * @param consistentRead * The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is used; * otherwise, an eventually consistent read is used. * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes withConsistentRead(Boolean consistentRead) { setConsistentRead(consistentRead); return this; } /** * <p> * The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is used; * otherwise, an eventually consistent read is used. * </p> * * @return The consistency of a read operation. If set to <code>true</code>, then a strongly consistent read is * used; otherwise, an eventually consistent read is used. */ public Boolean isConsistentRead() { return this.consistentRead; } /** * <p> * A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, * sets, or elements of a JSON document. The attributes in the <code>ProjectionExpression</code> must be separated * by commas. * </p> * <p> * If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are * not found, they will not appear in the result. * </p> * <p> * For more information, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @param projectionExpression * A string that identifies one or more attributes to retrieve from the table. These attributes can include * scalars, sets, or elements of a JSON document. The attributes in the <code>ProjectionExpression</code> * must be separated by commas.</p> * <p> * If no attribute names are specified, then all attributes will be returned. If any of the requested * attributes are not found, they will not appear in the result. * </p> * <p> * For more information, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. */ public void setProjectionExpression(String projectionExpression) { this.projectionExpression = projectionExpression; } /** * <p> * A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, * sets, or elements of a JSON document. The attributes in the <code>ProjectionExpression</code> must be separated * by commas. * </p> * <p> * If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are * not found, they will not appear in the result. * </p> * <p> * For more information, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @return A string that identifies one or more attributes to retrieve from the table. These attributes can include * scalars, sets, or elements of a JSON document. The attributes in the <code>ProjectionExpression</code> * must be separated by commas.</p> * <p> * If no attribute names are specified, then all attributes will be returned. If any of the requested * attributes are not found, they will not appear in the result. * </p> * <p> * For more information, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. */ public String getProjectionExpression() { return this.projectionExpression; } /** * <p> * A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, * sets, or elements of a JSON document. The attributes in the <code>ProjectionExpression</code> must be separated * by commas. * </p> * <p> * If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are * not found, they will not appear in the result. * </p> * <p> * For more information, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @param projectionExpression * A string that identifies one or more attributes to retrieve from the table. These attributes can include * scalars, sets, or elements of a JSON document. The attributes in the <code>ProjectionExpression</code> * must be separated by commas.</p> * <p> * If no attribute names are specified, then all attributes will be returned. If any of the requested * attributes are not found, they will not appear in the result. * </p> * <p> * For more information, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes withProjectionExpression(String projectionExpression) { setProjectionExpression(projectionExpression); return this; } /** * <p> * One or more substitution tokens for attribute names in an expression. The following are some use cases for using * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * To access an attribute whose name conflicts with a DynamoDB reserved word. * </p> * </li> * <li> * <p> * To create a placeholder for repeating occurrences of an attribute name in an expression. * </p> * </li> * <li> * <p> * To prevent special characters in an attribute name from being misinterpreted in an expression. * </p> * </li> * </ul> * <p> * Use the <b>#</b> character in an expression to dereference an attribute name. For example, consider the following * attribute name: * </p> * <ul> * <li> * <p> * <code>Percentile</code> * </p> * </li> * </ul> * <p> * The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For * the complete list of reserved words, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html">Reserved Words</a> in * the <i>Amazon DynamoDB Developer Guide</i>). To work around this, you could specify the following for * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * <code>{"#P":"Percentile"}</code> * </p> * </li> * </ul> * <p> * You could then use this substitution in an expression, as in this example: * </p> * <ul> * <li> * <p> * <code>#P = :val</code> * </p> * </li> * </ul> * <note> * <p> * Tokens that begin with the <b>:</b> character are <i>expression attribute values</i>, which are placeholders for * the actual value at runtime. * </p> * </note> * <p> * For more information on expression attribute names, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @return One or more substitution tokens for attribute names in an expression. The following are some use cases * for using <code>ExpressionAttributeNames</code>:</p> * <ul> * <li> * <p> * To access an attribute whose name conflicts with a DynamoDB reserved word. * </p> * </li> * <li> * <p> * To create a placeholder for repeating occurrences of an attribute name in an expression. * </p> * </li> * <li> * <p> * To prevent special characters in an attribute name from being misinterpreted in an expression. * </p> * </li> * </ul> * <p> * Use the <b>#</b> character in an expression to dereference an attribute name. For example, consider the * following attribute name: * </p> * <ul> * <li> * <p> * <code>Percentile</code> * </p> * </li> * </ul> * <p> * The name of this attribute conflicts with a reserved word, so it cannot be used directly in an * expression. (For the complete list of reserved words, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html">Reserved * Words</a> in the <i>Amazon DynamoDB Developer Guide</i>). To work around this, you could specify the * following for <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * <code>{"#P":"Percentile"}</code> * </p> * </li> * </ul> * <p> * You could then use this substitution in an expression, as in this example: * </p> * <ul> * <li> * <p> * <code>#P = :val</code> * </p> * </li> * </ul> * <note> * <p> * Tokens that begin with the <b>:</b> character are <i>expression attribute values</i>, which are * placeholders for the actual value at runtime. * </p> * </note> * <p> * For more information on expression attribute names, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. */ public java.util.Map<String, String> getExpressionAttributeNames() { return expressionAttributeNames; } /** * <p> * One or more substitution tokens for attribute names in an expression. The following are some use cases for using * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * To access an attribute whose name conflicts with a DynamoDB reserved word. * </p> * </li> * <li> * <p> * To create a placeholder for repeating occurrences of an attribute name in an expression. * </p> * </li> * <li> * <p> * To prevent special characters in an attribute name from being misinterpreted in an expression. * </p> * </li> * </ul> * <p> * Use the <b>#</b> character in an expression to dereference an attribute name. For example, consider the following * attribute name: * </p> * <ul> * <li> * <p> * <code>Percentile</code> * </p> * </li> * </ul> * <p> * The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For * the complete list of reserved words, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html">Reserved Words</a> in * the <i>Amazon DynamoDB Developer Guide</i>). To work around this, you could specify the following for * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * <code>{"#P":"Percentile"}</code> * </p> * </li> * </ul> * <p> * You could then use this substitution in an expression, as in this example: * </p> * <ul> * <li> * <p> * <code>#P = :val</code> * </p> * </li> * </ul> * <note> * <p> * Tokens that begin with the <b>:</b> character are <i>expression attribute values</i>, which are placeholders for * the actual value at runtime. * </p> * </note> * <p> * For more information on expression attribute names, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @param expressionAttributeNames * One or more substitution tokens for attribute names in an expression. The following are some use cases for * using <code>ExpressionAttributeNames</code>:</p> * <ul> * <li> * <p> * To access an attribute whose name conflicts with a DynamoDB reserved word. * </p> * </li> * <li> * <p> * To create a placeholder for repeating occurrences of an attribute name in an expression. * </p> * </li> * <li> * <p> * To prevent special characters in an attribute name from being misinterpreted in an expression. * </p> * </li> * </ul> * <p> * Use the <b>#</b> character in an expression to dereference an attribute name. For example, consider the * following attribute name: * </p> * <ul> * <li> * <p> * <code>Percentile</code> * </p> * </li> * </ul> * <p> * The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. * (For the complete list of reserved words, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html">Reserved * Words</a> in the <i>Amazon DynamoDB Developer Guide</i>). To work around this, you could specify the * following for <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * <code>{"#P":"Percentile"}</code> * </p> * </li> * </ul> * <p> * You could then use this substitution in an expression, as in this example: * </p> * <ul> * <li> * <p> * <code>#P = :val</code> * </p> * </li> * </ul> * <note> * <p> * Tokens that begin with the <b>:</b> character are <i>expression attribute values</i>, which are * placeholders for the actual value at runtime. * </p> * </note> * <p> * For more information on expression attribute names, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. */ public void setExpressionAttributeNames(java.util.Map<String, String> expressionAttributeNames) { this.expressionAttributeNames = expressionAttributeNames; } /** * <p> * One or more substitution tokens for attribute names in an expression. The following are some use cases for using * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * To access an attribute whose name conflicts with a DynamoDB reserved word. * </p> * </li> * <li> * <p> * To create a placeholder for repeating occurrences of an attribute name in an expression. * </p> * </li> * <li> * <p> * To prevent special characters in an attribute name from being misinterpreted in an expression. * </p> * </li> * </ul> * <p> * Use the <b>#</b> character in an expression to dereference an attribute name. For example, consider the following * attribute name: * </p> * <ul> * <li> * <p> * <code>Percentile</code> * </p> * </li> * </ul> * <p> * The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For * the complete list of reserved words, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html">Reserved Words</a> in * the <i>Amazon DynamoDB Developer Guide</i>). To work around this, you could specify the following for * <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * <code>{"#P":"Percentile"}</code> * </p> * </li> * </ul> * <p> * You could then use this substitution in an expression, as in this example: * </p> * <ul> * <li> * <p> * <code>#P = :val</code> * </p> * </li> * </ul> * <note> * <p> * Tokens that begin with the <b>:</b> character are <i>expression attribute values</i>, which are placeholders for * the actual value at runtime. * </p> * </note> * <p> * For more information on expression attribute names, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * </p> * * @param expressionAttributeNames * One or more substitution tokens for attribute names in an expression. The following are some use cases for * using <code>ExpressionAttributeNames</code>:</p> * <ul> * <li> * <p> * To access an attribute whose name conflicts with a DynamoDB reserved word. * </p> * </li> * <li> * <p> * To create a placeholder for repeating occurrences of an attribute name in an expression. * </p> * </li> * <li> * <p> * To prevent special characters in an attribute name from being misinterpreted in an expression. * </p> * </li> * </ul> * <p> * Use the <b>#</b> character in an expression to dereference an attribute name. For example, consider the * following attribute name: * </p> * <ul> * <li> * <p> * <code>Percentile</code> * </p> * </li> * </ul> * <p> * The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. * (For the complete list of reserved words, see <a * href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html">Reserved * Words</a> in the <i>Amazon DynamoDB Developer Guide</i>). To work around this, you could specify the * following for <code>ExpressionAttributeNames</code>: * </p> * <ul> * <li> * <p> * <code>{"#P":"Percentile"}</code> * </p> * </li> * </ul> * <p> * You could then use this substitution in an expression, as in this example: * </p> * <ul> * <li> * <p> * <code>#P = :val</code> * </p> * </li> * </ul> * <note> * <p> * Tokens that begin with the <b>:</b> character are <i>expression attribute values</i>, which are * placeholders for the actual value at runtime. * </p> * </note> * <p> * For more information on expression attribute names, see <a href= * "https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html" * >Accessing Item Attributes</a> in the <i>Amazon DynamoDB Developer Guide</i>. * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes withExpressionAttributeNames(java.util.Map<String, String> expressionAttributeNames) { setExpressionAttributeNames(expressionAttributeNames); return this; } public KeysAndAttributes addExpressionAttributeNamesEntry(String key, String value) { if (null == this.expressionAttributeNames) { this.expressionAttributeNames = new java.util.HashMap<String, String>(); } if (this.expressionAttributeNames.containsKey(key)) throw new IllegalArgumentException("Duplicated keys (" + key.toString() + ") are provided."); this.expressionAttributeNames.put(key, value); return this; } /** * Removes all the entries added into ExpressionAttributeNames. * * @return Returns a reference to this object so that method calls can be chained together. */ public KeysAndAttributes clearExpressionAttributeNamesEntries() { this.expressionAttributeNames = null; return this; } /** * Returns a string representation of this object. This is useful for testing and debugging. Sensitive data will be * redacted from this string using a placeholder value. * * @return A string representation of this object. * * @see java.lang.Object#toString() */ @Override public String toString() { StringBuilder sb = new StringBuilder(); sb.append("{"); if (getKeys() != null) sb.append("Keys: ").append(getKeys()).append(","); if (getAttributesToGet() != null) sb.append("AttributesToGet: ").append(getAttributesToGet()).append(","); if (getConsistentRead() != null) sb.append("ConsistentRead: ").append(getConsistentRead()).append(","); if (getProjectionExpression() != null) sb.append("ProjectionExpression: ").append(getProjectionExpression()).append(","); if (getExpressionAttributeNames() != null) sb.append("ExpressionAttributeNames: ").append(getExpressionAttributeNames()); sb.append("}"); return sb.toString(); } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (obj instanceof KeysAndAttributes == false) return false; KeysAndAttributes other = (KeysAndAttributes) obj; if (other.getKeys() == null ^ this.getKeys() == null) return false; if (other.getKeys() != null && other.getKeys().equals(this.getKeys()) == false) return false; if (other.getAttributesToGet() == null ^ this.getAttributesToGet() == null) return false; if (other.getAttributesToGet() != null && other.getAttributesToGet().equals(this.getAttributesToGet()) == false) return false; if (other.getConsistentRead() == null ^ this.getConsistentRead() == null) return false; if (other.getConsistentRead() != null && other.getConsistentRead().equals(this.getConsistentRead()) == false) return false; if (other.getProjectionExpression() == null ^ this.getProjectionExpression() == null) return false; if (other.getProjectionExpression() != null && other.getProjectionExpression().equals(this.getProjectionExpression()) == false) return false; if (other.getExpressionAttributeNames() == null ^ this.getExpressionAttributeNames() == null) return false; if (other.getExpressionAttributeNames() != null && other.getExpressionAttributeNames().equals(this.getExpressionAttributeNames()) == false) return false; return true; } @Override public int hashCode() { final int prime = 31; int hashCode = 1; hashCode = prime * hashCode + ((getKeys() == null) ? 0 : getKeys().hashCode()); hashCode = prime * hashCode + ((getAttributesToGet() == null) ? 0 : getAttributesToGet().hashCode()); hashCode = prime * hashCode + ((getConsistentRead() == null) ? 0 : getConsistentRead().hashCode()); hashCode = prime * hashCode + ((getProjectionExpression() == null) ? 0 : getProjectionExpression().hashCode()); hashCode = prime * hashCode + ((getExpressionAttributeNames() == null) ? 0 : getExpressionAttributeNames().hashCode()); return hashCode; } @Override public KeysAndAttributes clone() { try { return (KeysAndAttributes) super.clone(); } catch (CloneNotSupportedException e) { throw new IllegalStateException( "Got a CloneNotSupportedException from Object.clone() " + "even though we're Cloneable!", e); } } @com.amazonaws.annotation.SdkInternalApi @Override public void marshall(ProtocolMarshaller protocolMarshaller) { com.amazonaws.services.dynamodbv2.model.transform.KeysAndAttributesMarshaller.getInstance().marshall(this, protocolMarshaller); } }