Java tutorial
/* * Copyright 2015-2015 Amazon Technologies, Inc. * * Licensed 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://aws.amazon.com/apache2.0 * * 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.xspec; import java.util.Collections; import java.util.Map; import org.apache.http.annotation.Immutable; import com.amazonaws.annotation.Beta; /** * Expression specification for making GetItem request to Amazon DynamoDB. */ @Beta @Immutable public final class GetItemExpressionSpec extends ExpressionSpec { private final String projectionExpression; private final Map<String, String> nameMap; GetItemExpressionSpec(ExpressionSpecBuilder builder) { SubstitutionContext context = new SubstitutionContext(); this.projectionExpression = builder.buildProjectionExpression(context); final Map<String, String> nameMap = context.getNameMap(); this.nameMap = nameMap == null ? null : Collections.unmodifiableMap(nameMap); } /** * Returns the projection expression; or null if there is none. */ public final String getProjectionExpression() { return projectionExpression; } /** * Returns the name map which is unmodifiable; or null if there is none. */ @Override public final Map<String, String> getNameMap() { return nameMap; } }