com.cognitect.transit.impl.JsonParser Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of transit-java Show documentation
Show all versions of transit-java Show documentation
Transit is a data format and a set of libraries for conveying values between applications written in different languages. This library provides support for marshalling Transit data to/from Java.
// Copyright (c) Cognitect, Inc.
// All rights reserved.
package com.cognitect.transit.impl;
import com.cognitect.transit.*;
import com.fasterxml.jackson.core.JsonToken;
import java.io.EOFException;
import java.io.IOException;
import java.math.BigInteger;
import java.util.List;
import java.util.Map;
public class JsonParser extends AbstractParser {
private final com.fasterxml.jackson.core.JsonParser jp;
public JsonParser(com.fasterxml.jackson.core.JsonParser jp,
Map> handlers,
DefaultReadHandler defaultHandler,
MapReader, Object, Object> mapBuilder,
ArrayReader, Object> listBuilder) {
super(handlers, defaultHandler, mapBuilder, listBuilder);
this.jp = jp;
}
private Object parseLong() throws IOException {
Object val;
try {
val = jp.getLongValue();
}catch(IOException e) {
val = new BigInteger(jp.getText());
}
return val;
}
@Override
public Object parse(ReadCache cache) throws IOException {
if(jp.nextToken() == null)
throw new EOFException();
else
return parseVal(false, cache);
}
@Override
public Object parseVal(boolean asMapKey, ReadCache cache) throws IOException {
switch(jp.getCurrentToken()) {
case START_OBJECT:
return parseMap(asMapKey, cache, null);
case START_ARRAY:
return parseArray(asMapKey, cache, null);
case FIELD_NAME:
return cache.cacheRead(jp.getText(), asMapKey, this);
case VALUE_STRING:
return cache.cacheRead(jp.getText(), asMapKey, this);
case VALUE_NUMBER_INT:
return parseLong();
case VALUE_NUMBER_FLOAT:
return jp.getDoubleValue();
case VALUE_TRUE:
return true;
case VALUE_FALSE:
return false;
case VALUE_NULL:
return null;
default: return null;
}
}
@Override
public Object parseMap(boolean ignored, ReadCache cache, MapReadHandler handler) throws IOException {
return parseMap(ignored, cache, handler, JsonToken.END_OBJECT);
}
public Object parseMap(boolean ignored, ReadCache cache, MapReadHandler handler, JsonToken endToken) throws IOException {
MapReader mr = (handler != null) ? handler.mapReader() : mapBuilder;
Object mb = mr.init();
while(jp.nextToken() != endToken) {
Object key = parseVal(true, cache);
if (key instanceof Tag) {
String tag = ((Tag) key).getValue();
ReadHandler val_handler = getHandler(tag);
Object val;
jp.nextToken(); // advance to read value
if (val_handler != null) {
if (this.jp.getCurrentToken() == JsonToken.START_OBJECT && val_handler instanceof MapReadHandler) {
// use map reader to decode value
val = parseMap(false, cache, (MapReadHandler) val_handler);
} else if (this.jp.getCurrentToken() == JsonToken.START_ARRAY && val_handler instanceof ArrayReadHandler) {
// use array reader to decode value
val = parseArray(false, cache, (ArrayReadHandler) val_handler);
} else {
// read value and decode normally
val = val_handler.fromRep(parseVal(false, cache));
}
} else {
// default decode
val = this.decode(tag, parseVal(false, cache));
}
jp.nextToken(); // advance to read end of object or array
return val;
} else {
jp.nextToken(); // advance to read value
mb = mr.add(mb, key, parseVal(false, cache));
}
}
return mr.complete(mb);
}
@Override
public Object parseArray(boolean ignored, ReadCache cache, ArrayReadHandler handler) throws IOException {
// if nextToken == JsonToken.END_ARRAY
if (jp.nextToken() != JsonToken.END_ARRAY) {
Object firstVal = parseVal(false, cache);
if (firstVal != null) {
if (firstVal == Constants.MAP_AS_ARRAY) {
// if the same, build a map w/ rest of array contents
return parseMap(false, cache, null, JsonToken.END_ARRAY);
} else if (firstVal instanceof Tag) {
String tag = ((Tag) firstVal).getValue();
ReadHandler val_handler = getHandler(tag);
jp.nextToken(); // advance to value
Object val;
if (val_handler != null) {
if (this.jp.getCurrentToken() == JsonToken.START_OBJECT && val_handler instanceof MapReadHandler) {
// use map reader to decode value
val = parseMap(false, cache, (MapReadHandler) val_handler);
} else if (this.jp.getCurrentToken() == JsonToken.START_ARRAY && val_handler instanceof ArrayReadHandler) {
// use array reader to decode value
val = parseArray(false, cache, (ArrayReadHandler) val_handler);
} else {
// read value and decode normally
val = val_handler.fromRep(parseVal(false, cache));
}
} else {
// default decode
val = this.decode(tag, parseVal(false, cache));
}
jp.nextToken(); // advance past end of object or array
return val;
}
}
// process array w/o special decoding or interpretation
ArrayReader ar = (handler != null) ? handler.arrayReader() : listBuilder;
Object ab = ar.init();
ab = ar.add(ab, firstVal);
while (jp.nextToken() != JsonToken.END_ARRAY) {
ab = ar.add(ab, parseVal(false, cache));
}
return ar.complete(ab);
}
// make an empty collection, honoring handler's arrayReader, if present
ArrayReader ar = (handler != null) ? handler.arrayReader() : listBuilder;
return ar.complete(ar.init(0));
}
}