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/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you 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.
*/
package org.elasticsearch.common.xcontent;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.ParseFieldMatcherSupplier;
import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.xcontent.ObjectParser.ValueType;
import org.elasticsearch.common.xcontent.json.JsonXContent;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
/**
* Superclass for {@link ObjectParser} and {@link ConstructingObjectParser}. Defines most of the "declare" methods so they can be shared.
*/
public abstract class AbstractObjectParser
implements BiFunction {
/**
* Reads an object from a parser using some context.
*/
@FunctionalInterface
public interface ContextParser {
T parse(XContentParser p, Context c) throws IOException;
}
/**
* Reads an object right from the parser without any context.
*/
@FunctionalInterface
public interface NoContextParser {
T parse(XContentParser p) throws IOException;
}
/**
* Declare some field. Usually it is easier to use {@link #declareString(BiConsumer, ParseField)} or
* {@link #declareObject(BiConsumer, BiFunction, ParseField)} rather than call this directly.
*/
public abstract void declareField(BiConsumer consumer, ContextParser parser, ParseField parseField,
ValueType type);
public void declareField(BiConsumer consumer, NoContextParser parser, ParseField parseField, ValueType type) {
if (parser == null) {
throw new IllegalArgumentException("[parser] is required");
}
declareField(consumer, (p, c) -> parser.parse(p), parseField, type);
}
public void declareObject(BiConsumer consumer, BiFunction objectParser, ParseField field) {
declareField(consumer, (p, c) -> objectParser.apply(p, c), field, ValueType.OBJECT);
}
public void declareFloat(BiConsumer consumer, ParseField field) {
// Using a method reference here angers some compilers
declareField(consumer, p -> p.floatValue(), field, ValueType.FLOAT);
}
public void declareDouble(BiConsumer consumer, ParseField field) {
// Using a method reference here angers some compilers
declareField(consumer, p -> p.doubleValue(), field, ValueType.DOUBLE);
}
public void declareLong(BiConsumer consumer, ParseField field) {
// Using a method reference here angers some compilers
declareField(consumer, p -> p.longValue(), field, ValueType.LONG);
}
public void declareInt(BiConsumer consumer, ParseField field) {
// Using a method reference here angers some compilers
declareField(consumer, p -> p.intValue(), field, ValueType.INT);
}
public void declareString(BiConsumer consumer, ParseField field) {
declareField(consumer, XContentParser::text, field, ValueType.STRING);
}
public void declareStringOrNull(BiConsumer consumer, ParseField field) {
declareField(consumer, (p) -> p.currentToken() == XContentParser.Token.VALUE_NULL ? null : p.text(), field,
ValueType.STRING_OR_NULL);
}
public void declareBoolean(BiConsumer consumer, ParseField field) {
declareField(consumer, XContentParser::booleanValue, field, ValueType.BOOLEAN);
}
public void declareObjectArray(BiConsumer> consumer, BiFunction objectParser,
ParseField field) {
declareField(consumer, (p, c) -> parseArray(p, () -> objectParser.apply(p, c)), field, ValueType.OBJECT_ARRAY);
}
public void declareStringArray(BiConsumer> consumer, ParseField field) {
declareField(consumer, (p, c) -> parseArray(p, p::text), field, ValueType.STRING_ARRAY);
}
public void declareDoubleArray(BiConsumer> consumer, ParseField field) {
declareField(consumer, (p, c) -> parseArray(p, p::doubleValue), field, ValueType.DOUBLE_ARRAY);
}
public void declareFloatArray(BiConsumer> consumer, ParseField field) {
declareField(consumer, (p, c) -> parseArray(p, p::floatValue), field, ValueType.FLOAT_ARRAY);
}
public void declareLongArray(BiConsumer> consumer, ParseField field) {
declareField(consumer, (p, c) -> parseArray(p, p::longValue), field, ValueType.LONG_ARRAY);
}
public void declareIntArray(BiConsumer> consumer, ParseField field) {
declareField(consumer, (p, c) -> parseArray(p, p::intValue), field, ValueType.INT_ARRAY);
}
public void declareRawObject(BiConsumer consumer, ParseField field) {
NoContextParser bytesParser = p -> {
try (XContentBuilder builder = JsonXContent.contentBuilder()) {
builder.prettyPrint();
builder.copyCurrentStructure(p);
return builder.bytes();
}
};
declareField(consumer, bytesParser, field, ValueType.OBJECT);
}
private interface IOSupplier {
T get() throws IOException;
}
private static List parseArray(XContentParser parser, IOSupplier supplier) throws IOException {
List list = new ArrayList<>();
if (parser.currentToken().isValue()) {
list.add(supplier.get()); // single value
} else {
while (parser.nextToken() != XContentParser.Token.END_ARRAY) {
if (parser.currentToken().isValue() || parser.currentToken() == XContentParser.Token.START_OBJECT) {
list.add(supplier.get());
} else {
throw new IllegalStateException("expected value but got [" + parser.currentToken() + "]");
}
}
}
return list;
}
}