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package org.json.stream; /* Copyright (c) 2002 JSON.org Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. The Software shall be used for Good, not Evil. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import org.json.JSONParseException; import org.json.stream.JSONStreamReader.ParseState; import org.json.util.ALStack; import java.io.InputStream; import java.io.Reader; import java.nio.charset.Charset; /** * Builds a JSON object model using events supplied from {@link JSONStreamReader}. * This uses minimal stack space than parsing via {@link org.json.JSONTokener}, * since only a few stack frames are allocated, by using a trampoline. * * @author JSON.org * @version 2016-08-01 */ public final class JSONLimitBuilder { private static final BuilderLimits DEFAULT_PARAMS = new BuilderLimits(); private JSONLimitBuilder() { } /** * Build a JSON value from a {@code Reader}. The value may be one of: *

* * @param reader A reader. * @param params the limits imposed on the builder * @return a JSON value of the type defined above */ public static Object buildJSONValue(Reader reader, BuilderLimits params) throws JSONException { return buildJSONValue(new JSONLimitStreamReader(reader), params); } /** * Build a JSON value from a {@code Reader}. The value may be one of: * * * @param reader A reader. * @return a JSON value of the type defined above */ public static Object buildJSONValue(Reader reader) throws JSONException { return buildJSONValue(new JSONLimitStreamReader(reader), DEFAULT_PARAMS); } /** * Build a JSON value from a {@code InputStream} and supplied * {@code Charset}. The value may be one of: * * * @param inputStream the input stream containing the JSON data * @param charset the character set with which to interpret the * input stream * @param params the limits imposed on the builder * @return a JSON value of the type defined above */ public static Object buildJSONValue(InputStream inputStream, Charset charset, BuilderLimits params) throws JSONException { return buildJSONValue(new JSONLimitStreamReader(inputStream, charset), params); } /** * Build a JSON value from a {@code InputStream} and supplied * {@code Charset}. The value may be one of: * * * @param inputStream the input stream containing the JSON data * @param charset the character set with which to interpret the * input stream * @return a JSON value of the type defined above */ public static Object buildJSONValue(InputStream inputStream, Charset charset) throws JSONException { return buildJSONValue(new JSONLimitStreamReader(inputStream, charset), DEFAULT_PARAMS); } /** * Build a JSON value from a {@code String}. The value may be one of: * * * @param s A source string. * @param params the limits imposed on the builder * @return a JSON value of the type defined above */ public static Object buildJSONValue(String s, BuilderLimits params) throws JSONException { return buildJSONValue(new JSONLimitStreamReader(s), params); } /** * Build a JSON value from a {@code String}. The value may be one of: * * * @param s A source string. * @return a JSON value of the type defined above */ public static Object buildJSONValue(String s) throws JSONException { return buildJSONValue(new JSONLimitStreamReader(s), DEFAULT_PARAMS); } /** * Build a JSON value from a {@code JSONStreamReader}. The value may be one * of: * *

The reader must be at the beginning of the document.

* * @param reader A source stream. * @return a JSON value of the type defined above */ public static Object buildJSONValue(JSONLimitStreamReader reader) throws JSONException { return buildJSONValue(reader, DEFAULT_PARAMS); } /** * Build a JSON value from a {@code JSONStreamReader}. The value may be one * of: * *

The reader must be at the beginning of the document.

* * @param reader A source stream. * @param params the limits imposed on the builder * @return a JSON value of the type defined above */ public static Object buildJSONValue(JSONLimitStreamReader reader, BuilderLimits params) throws JSONException { reader.withLimits(params); ParseState state = reader.nextState(); if (state != ParseState.DOCUMENT) { throw new JSONParseException("JSON parser should be at the beginning", reader.getParsePosition()); } state = reader.nextState(); Object result; switch (state) { case OBJECT: result = parseObjectTree(reader, params); break; case ARRAY: result = parseArrayTree(reader, params); break; case NULL_VALUE: case BOOLEAN_VALUE: case NUMBER_VALUE: case STRING_VALUE: result = reader.nextValue(); break; default: throw new JSONParseException("Expected value", reader.getParsePosition()); } if (reader.nextState() != ParseState.END_DOCUMENT) { throw new JSONParseException("JSON parser in an unexpected state", reader.getParsePosition()); } return result; } /** * Build a JSONObject from a {@code Reader}. * * @param reader A reader. * @param params the limits imposed on the builder * @return a JSONObject value */ public static JSONObject buildJSONObject(Reader reader, BuilderLimits params) throws JSONException { return buildJSONObject(new JSONLimitStreamReader(reader), params); } public static JSONObject buildJSONObject(Reader reader) throws JSONException { return buildJSONObject(new JSONLimitStreamReader(reader), DEFAULT_PARAMS); } /** * Build a JSONObject from a {@code InputStream} and supplied * {@code Charset}. * * @param inputStream the input stream containing the JSON data * @param charset the character set with which to interpret the * input stream * @param params the limits imposed on the builder * @return a JSONObject value */ public static JSONObject buildJSONObject(InputStream inputStream, Charset charset, BuilderLimits params) throws JSONException { return buildJSONObject(new JSONLimitStreamReader(inputStream, charset), params); } public static JSONObject buildJSONObject(InputStream inputStream, Charset charset) throws JSONException { return buildJSONObject(new JSONLimitStreamReader(inputStream, charset), DEFAULT_PARAMS); } /** * Build a JSONObject from a {@code String}. * * @param s A source string. * @param params the limits imposed on the builder * @return a JSONObject value */ public static JSONObject buildJSONObject(String s, BuilderLimits params) throws JSONException { return buildJSONObject(new JSONLimitStreamReader(s), params); } public static JSONObject buildJSONObject(String s) throws JSONException { return buildJSONObject(new JSONLimitStreamReader(s), DEFAULT_PARAMS); } public static JSONObject buildJSONObject(JSONLimitStreamReader reader) throws JSONException { return buildJSONObject(reader, DEFAULT_PARAMS); } /** * Build a JSONObject from a {@code JSONStreamReader}. The reader must be * at the beginning of the document. * * @param reader A source stream. * @param params the limits imposed on the builder * @return a JSONObject value */ public static JSONObject buildJSONObject(JSONLimitStreamReader reader, BuilderLimits params) throws JSONException { reader.withLimits(params); ParseState state = reader.nextState(); if(state != ParseState.DOCUMENT) { throw new JSONParseException("JSON parser should be at the beginning", reader.getParsePosition()); } JSONObject result; state = reader.nextState(); switch(state) { case OBJECT: result = parseObjectTree(reader, params); break; default: throw new JSONParseException("Expected object", reader.getParsePosition()); } if(reader.nextState() != ParseState.END_DOCUMENT) { throw new JSONParseException("JSON parser in an unexpected state", reader.getParsePosition()); } return result; } /** * Build a JSONArray from a {@code Reader}. * * @param reader A reader. * @param params the limits imposed on the builder * @return a JSONArray value */ public static JSONArray buildJSONArray(Reader reader, BuilderLimits params) throws JSONException { return buildJSONArray(new JSONLimitStreamReader(reader), params); } public static JSONArray buildJSONArray(Reader reader) throws JSONException { return buildJSONArray(new JSONLimitStreamReader(reader), DEFAULT_PARAMS); } /** * Build a JSONArray from a {@code InputStream} and supplied * {@code Charset}. * * @param inputStream the input stream containing the JSON data * @param charset the character set with which to interpret the * input stream * @param params the limits imposed on the builder * @return a JSONArray value */ public static JSONArray buildJSONArray(InputStream inputStream, Charset charset, BuilderLimits params) throws JSONException { return buildJSONArray(new JSONLimitStreamReader(inputStream, charset), params); } public static JSONArray buildJSONArray(InputStream inputStream, Charset charset) throws JSONException { return buildJSONArray(new JSONLimitStreamReader(inputStream, charset), DEFAULT_PARAMS); } /** * Build a JSONArray from a {@code String}. * * @param s A source string. * @param params the limits imposed on the builder * @return a JSONArray value */ public static JSONArray buildJSONArray(String s, BuilderLimits params) throws JSONException { return buildJSONArray(new JSONLimitStreamReader(s), params); } public static JSONArray buildJSONArray(String s) throws JSONException { return buildJSONArray(new JSONLimitStreamReader(s), DEFAULT_PARAMS); } public static JSONArray buildJSONArray(JSONLimitStreamReader reader) throws JSONException { return buildJSONArray(reader, DEFAULT_PARAMS); } /** * Build a JSONArray from a {@code JSONStreamReader}. The reader must be * at the beginning of the document. * * @param reader A source stream. * @param params the limits imposed on the builder * @return a JSONArray value */ public static JSONArray buildJSONArray(JSONLimitStreamReader reader, BuilderLimits params) throws JSONException { reader.withLimits(params); ParseState state = reader.nextState(); if(state != ParseState.DOCUMENT) { throw new JSONParseException("JSON parser should be at the beginning", reader.getParsePosition()); } JSONArray result; state = reader.nextState(); switch(state) { case ARRAY: result = parseArrayTree(reader, params); break; default: throw new JSONParseException("Expected array", reader.getParsePosition()); } if(reader.nextState() != ParseState.END_DOCUMENT) { throw new JSONParseException("JSON parser in an unexpected state", reader.getParsePosition()); } return result; } /** * Iterate over a stack of StructureBuilder objects, starting from an * initial {@code JSONArray} builder. Using this type of iterative approach * instead of recursion is known as trampolining. * * @param reader the stream reader * @param params the limits imposed on the builder * @return the populated JSON array */ private static JSONArray parseArrayTree(JSONLimitStreamReader reader, BuilderLimits params) throws JSONException { JSONArray array = new JSONArray(); ALStack stack = new ALStack(); stack.push(new StructureArrayBuilder(array, params)); ParseState state; try { while(!stack.isEmpty()) { state = reader.nextState(); stack.peek().accept(state, stack, reader); } } catch (RuntimeException e) { throw new JSONParseException(e.getMessage() + ", at " + JSONPointerUtils.toJSONPointer(stack), reader.getParsePosition()); } return array; } /** * Iterate over a stack of StructureBuilder objects, starting from an * initial {@code JSONObject} builder. Using this type of iterative approach * instead of recursion is known as trampolining. * * @param reader the stream reader * @param params the limits imposed on the builder * @return the populated JSON object */ private static JSONObject parseObjectTree(JSONLimitStreamReader reader, BuilderLimits params) throws JSONException { JSONObject object = new JSONObject(); ALStack stack = new ALStack(); stack.push(new StructureObjectBuilder(object, params)); ParseState state; try { while(!stack.isEmpty()) { state = reader.nextState(); stack.peek().accept(state, stack, reader); } } catch (RuntimeException e) { throw new JSONParseException(e.getMessage() + ", at " + JSONPointerUtils.toJSONPointer(stack), reader.getParsePosition()); } return object; } }