com.arangodb.velocypack.VPackParser Maven / Gradle / Ivy
/*
* DISCLAIMER
*
* Copyright 2016 ArangoDB GmbH, Cologne, Germany
*
* 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://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License 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.
*
* Copyright holder is ArangoDB GmbH, Cologne, Germany
*/
package com.arangodb.velocypack;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import org.json.simple.JSONValue;
import org.json.simple.parser.ContentHandler;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;
import com.arangodb.velocypack.exception.VPackBuilderException;
import com.arangodb.velocypack.exception.VPackException;
/**
* @author Mark - mark at arangodb.com
*
*/
public class VPackParser {
private static final char OBJECT_OPEN = '{';
private static final char OBJECT_CLOSE = '}';
private static final char ARRAY_OPEN = '[';
private static final char ARRAY_CLOSE = ']';
private static final char FIELD = ':';
private static final char SEPARATOR = ',';
private static final String NULL = "null";
private final Map deserializers;
private final Map> deserializersByName;
public VPackParser() {
super();
deserializers = new HashMap();
deserializersByName = new HashMap>();
}
public String toJson(final VPackSlice vpack) throws VPackException {
return toJson(vpack, false);
}
public String toJson(final VPackSlice vpack, final boolean includeNullValues) throws VPackException {
final StringBuilder json = new StringBuilder();
parse(null, null, vpack, json, includeNullValues);
return json.toString();
}
public VPackParser registerDeserializer(
final String attribute,
final ValueType type,
final VPackJsonDeserializer deserializer) {
Map byName = deserializersByName.get(attribute);
if (byName == null) {
byName = new HashMap();
deserializersByName.put(attribute, byName);
}
byName.put(type, deserializer);
return this;
}
public VPackParser registerDeserializer(final ValueType type, final VPackJsonDeserializer deserializer) {
deserializers.put(type, deserializer);
return this;
}
private VPackJsonDeserializer getDeserializer(final String attribute, final ValueType type) {
VPackJsonDeserializer deserializer = null;
final Map byName = deserializersByName.get(attribute);
if (byName != null) {
deserializer = byName.get(type);
}
if (deserializer == null) {
deserializer = deserializers.get(type);
}
return deserializer;
}
private void parse(
final VPackSlice parent,
final String attribute,
final VPackSlice value,
final StringBuilder json,
final boolean includeNullValues) throws VPackException {
VPackJsonDeserializer deserializer = null;
if (attribute != null) {
appendField(attribute, json);
deserializer = getDeserializer(attribute, value.type());
}
if (deserializer != null) {
deserializer.deserialize(parent, attribute, value, json);
} else {
if (value.isObject()) {
parseObject(value, json, includeNullValues);
} else if (value.isArray()) {
parseArray(value, json, includeNullValues);
} else if (value.isBoolean()) {
json.append(value.getAsBoolean());
} else if (value.isString()) {
json.append(JSONValue.toJSONString(value.getAsString()));
} else if (value.isNumber()) {
json.append(value.getAsNumber());
} else if (value.isNull()) {
json.append(NULL);
} else {
json.append(NULL);
}
}
}
private static void appendField(final String attribute, final StringBuilder json) {
json.append(JSONValue.toJSONString(attribute));
json.append(FIELD);
}
private void parseObject(final VPackSlice value, final StringBuilder json, final boolean includeNullValues)
throws VPackException {
json.append(OBJECT_OPEN);
int added = 0;
for (final Iterator> iterator = value.objectIterator(); iterator.hasNext();) {
final Entry next = iterator.next();
final VPackSlice nextValue = next.getValue();
if (!nextValue.isNull() || includeNullValues) {
if (added++ > 0) {
json.append(SEPARATOR);
}
parse(value, next.getKey(), nextValue, json, includeNullValues);
}
}
json.append(OBJECT_CLOSE);
}
private void parseArray(final VPackSlice value, final StringBuilder json, final boolean includeNullValues)
throws VPackException {
json.append(ARRAY_OPEN);
int added = 0;
for (int i = 0; i < value.getLength(); i++) {
final VPackSlice valueAt = value.get(i);
if (!valueAt.isNull() || includeNullValues) {
if (added++ > 0) {
json.append(SEPARATOR);
}
parse(value, null, valueAt, json, includeNullValues);
}
}
json.append(ARRAY_CLOSE);
}
public VPackSlice fromJson(final String json) throws VPackException {
return fromJson(json, false);
}
public VPackSlice fromJson(final String json, final boolean includeNullValues) throws VPackException {
final VPackBuilder builder = new VPackBuilder();
final JSONParser parser = new JSONParser();
final ContentHandler contentHandler = new VPackContentHandler(builder, includeNullValues);
try {
parser.parse(json, contentHandler);
} catch (final ParseException e) {
throw new VPackBuilderException(e);
}
return builder.slice();
}
private static class VPackContentHandler implements ContentHandler {
private final VPackBuilder builder;
private String attribute;
private final boolean includeNullValues;
public VPackContentHandler(final VPackBuilder builder, final boolean includeNullValues) {
this.builder = builder;
this.includeNullValues = includeNullValues;
attribute = null;
}
private void add(final ValueType value) throws ParseException {
try {
builder.add(attribute, value);
attribute = null;
} catch (final VPackBuilderException e) {
throw new ParseException(ParseException.ERROR_UNEXPECTED_EXCEPTION);
}
}
private void add(final String value) throws ParseException {
try {
builder.add(attribute, value);
attribute = null;
} catch (final VPackBuilderException e) {
throw new ParseException(ParseException.ERROR_UNEXPECTED_EXCEPTION);
}
}
private void add(final Boolean value) throws ParseException {
try {
builder.add(attribute, value);
attribute = null;
} catch (final VPackBuilderException e) {
throw new ParseException(ParseException.ERROR_UNEXPECTED_EXCEPTION);
}
}
private void add(final Double value) throws ParseException {
try {
builder.add(attribute, value);
attribute = null;
} catch (final VPackBuilderException e) {
throw new ParseException(ParseException.ERROR_UNEXPECTED_EXCEPTION);
}
}
private void add(final Long value) throws ParseException {
try {
builder.add(attribute, value);
attribute = null;
} catch (final VPackBuilderException e) {
throw new ParseException(ParseException.ERROR_UNEXPECTED_EXCEPTION);
}
}
private void close() throws ParseException {
try {
builder.close();
} catch (final VPackBuilderException e) {
throw new ParseException(ParseException.ERROR_UNEXPECTED_EXCEPTION);
}
}
@Override
public void startJSON() throws ParseException, IOException {
}
@Override
public void endJSON() throws ParseException, IOException {
}
@Override
public boolean startObject() throws ParseException, IOException {
add(ValueType.OBJECT);
return true;
}
@Override
public boolean endObject() throws ParseException, IOException {
close();
return true;
}
@Override
public boolean startObjectEntry(final String key) throws ParseException, IOException {
attribute = key;
return true;
}
@Override
public boolean endObjectEntry() throws ParseException, IOException {
return true;
}
@Override
public boolean startArray() throws ParseException, IOException {
add(ValueType.ARRAY);
return true;
}
@Override
public boolean endArray() throws ParseException, IOException {
close();
return true;
}
@Override
public boolean primitive(final Object value) throws ParseException, IOException {
if (value == null) {
if (includeNullValues) {
add(ValueType.NULL);
}
} else if (String.class.isAssignableFrom(value.getClass())) {
add(String.class.cast(value));
} else if (Boolean.class.isAssignableFrom(value.getClass())) {
add(Boolean.class.cast(value));
} else if (Double.class.isAssignableFrom(value.getClass())) {
add(Double.class.cast(value));
} else if (Number.class.isAssignableFrom(value.getClass())) {
add(Long.class.cast(value));
}
return true;
}
}
} © 2015 - 2025 Weber Informatics LLC | Privacy Policy