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/* * Copyright 2010-2019 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.transform; import java.io.IOException; import java.util.Collections; import java.util.Map; import com.amazonaws.http.HttpResponse; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonToken; /** * Used effectively as the API to access the context of performing the * json-related unmarshalling. * <p> * For full support, see {@link JsonUnmarshallerContextImpl} * </p> */ public abstract class JsonUnmarshallerContext { public enum UnmarshallerType { /** * @see SimpleTypeJsonUnmarshallers.JsonValueStringUnmarshaller */ JSON_VALUE } /** * Returns the value of the header with the specified name from the * response, or null if not present. * * @param header * The name of the header to lookup. * * @return The value of the header with the specified name from the * response. Returns null by default or if the header is not * present. */ public String getHeader(String header) { return null; } /** * Returns the original HttpResponse constructed for this request. Returns * null by default. */ public HttpResponse getHttpResponse() { return null; } /** * Returns the element depth of the parser's current position in the JSON * document being parsed. * * @return The element depth of the parser's current position in the JSON * document being parsed. Returns -1 by default. */ public int getCurrentDepth() { return -1; } /** * Returns the text of the current token, or throws an exception if the * current token does not contain text (ex: '{', '}', etc.). * * @return The text of the current token. Returns null by default. * * @throws IOException */ public String readText() throws IOException { return null; } /** * Returns true if parsing of the Json document is yet to start. Returns * false by default or if the parsing of Json document is not yet started. */ public boolean isStartOfDocument() { return false; } /** * Tests the specified expression (a JSON field name) against the current * position in the JSON document being parsed. * * @param expression * The field name to test. * @return True if the expression matches the current document position, * Returns false by default and in all other cases. */ public boolean testExpression(String expression) { return false; } /** * Returns the name of the JSON field that is the nearest parent of the * current context.Returns null by default. */ public String getCurrentParentElement() { return null; } /** * Tests the specified expression (a JSON field name) against the current * position in the JSON document being parsed, and restricts the expression * to matching at the specified stack depth. * * @param expression * The field name to test. * @param stackDepth * The depth in the stack representing where the expression must * start matching in order for this method to return true. * * @return True if the specified expression matches the current position in * the JSON document, starting from the specified depth. Returns * false by default. */ public boolean testExpression(String expression, int stackDepth) { return false; } /** * Returns the next JsonToken from the JsonParser. Returns null by default. */ public JsonToken nextToken() throws IOException { return null; } /** * Returns the JsonToken which is to be parsed next. Returns null by * default. */ public JsonToken peek() throws IOException { return null; } /** * Returns the JsonParser used for parsing the Json document. Returns null * by default. */ public JsonParser getJsonParser() { return null; } /** * Returns any metadata collected through metadata expressions while this * context was reading the JSON events from the JSON document. * * @return A map of any metadata collected through metadata expressions * while this context was reading the JSON document. Returns an * empty map by default. */ public Map<String, String> getMetadata() { return Collections.emptyMap(); } /** * Registers an expression, which if matched, will cause the data for the * matching element to be stored in the metadata map under the specified * key. * * @param expression * The expression an element must match in order for it's data to * be pulled out and stored in the metadata map. * @param targetDepth * The depth in the JSON document where the expression match must * start. * @param storageKey * The key under which to store the matching element's data. */ public void registerMetadataExpression(String expression, int targetDepth, String storageKey) { } /** * Sets the name of the response header that is to be read next. */ public void setCurrentHeader(String currentHeader) { } /** * Returns the current JsonToken that is to be parsed by the parser. Returns * null by default. */ public JsonToken getCurrentToken() { return null; } /** * This will return the deleted string in stackString when doing update on * the stack. Returns null by default. */ public String getLastParsedParentElement() { return null; } /** * Returns true if the <code>JsonUnmarshallerContext</code> is involved in * parsing response headers. Else returns false. Returns true by default. */ public boolean isInsideResponseHeader() { return true; } /** * Returns the JsonUnmarshaller for the specified scalar type. Returns null by default. */ public <T> Unmarshaller<T, JsonUnmarshallerContext> getUnmarshaller(Class<T> type) { return null; } /** * Returns the JsonUnmarshaller for requested custom unmarshaller type. Returns null by default. */ public <T> Unmarshaller<T, JsonUnmarshallerContext> getUnmarshaller(Class<T> type, UnmarshallerType unmarshallerType) { return null; } }