com.fasterxml.jackson.xml.deser.FromXmlParser Maven / Gradle / Ivy
package com.fasterxml.jackson.xml.deser;
import java.io.IOException;
import java.math.BigDecimal;
import java.math.BigInteger;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamWriter;
import org.codehaus.jackson.Base64Variant;
import org.codehaus.jackson.JsonLocation;
import org.codehaus.jackson.JsonParseException;
import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.JsonToken;
import org.codehaus.jackson.ObjectCodec;
import org.codehaus.jackson.impl.JsonParserMinimalBase;
import org.codehaus.jackson.impl.JsonReadContext;
import org.codehaus.jackson.io.IOContext;
import org.codehaus.jackson.util.ByteArrayBuilder;
import com.fasterxml.jackson.xml.util.XmlTokenStream;
/**
* {@link JsonParser} implementation that exposes XML structure as
* set of JSON events that can be used for data binding.
*
* @since 1.6
*/
public class FromXmlParser
extends JsonParserMinimalBase
{
/**
* Enumeration that defines all togglable features for XML parsers
*/
public enum Feature {
DUMMY_PLACEHOLDER(false)
;
final boolean _defaultState;
final int _mask;
/**
* Method that calculates bit set (flags) of all features that
* are enabled by default.
*/
public static int collectDefaults()
{
int flags = 0;
for (Feature f : values()) {
if (f.enabledByDefault()) {
flags |= f.getMask();
}
}
return flags;
}
private Feature(boolean defaultState) {
_defaultState = defaultState;
_mask = (1 << ordinal());
}
public boolean enabledByDefault() { return _defaultState; }
public int getMask() { return _mask; }
}
/**
* In cases where a start element has both attributes and non-empty textual
* value, we have to create a bogus property; we will use this as
* the property name.
*/
protected final static String UNNAMED_TEXT_PROPERTY = "";
/*
/**********************************************************
/* Configuration
/**********************************************************
*/
/**
* Bit flag composed of bits that indicate which
* {@link FromXmlParser.Feature}s
* are enabled.
*/
protected int _xmlFeatures;
protected ObjectCodec _objectCodec;
/*
/**********************************************************
/* I/O state
/**********************************************************
*/
/**
* Flag that indicates whether parser is closed or not. Gets
* set when parser is either closed by explicit call
* ({@link #close}) or when end-of-input is reached.
*/
protected boolean _closed;
final protected IOContext _ioContext;
/*
/**********************************************************
/* Parsing state
/**********************************************************
*/
/**
* Information about parser context, context in which
* the next token is to be parsed (root, array, object).
*/
protected JsonReadContext _parsingContext;
protected final XmlTokenStream _xmlTokens;
/**
* We need special handling to keep track of whether a value
* may be exposed as simple leaf value.
*/
protected boolean _mayBeLeaf;
protected JsonToken _nextToken;
protected String _currText;
/*
/**********************************************************
/* Parsing state, parsed values
/**********************************************************
*/
/**
* ByteArrayBuilder is needed if 'getBinaryValue' is called. If so,
* we better reuse it for remainder of content.
*/
protected ByteArrayBuilder _byteArrayBuilder = null;
/**
* We will hold on to decoded binary data, for duration of
* current event, so that multiple calls to
* {@link #getBinaryValue} will not need to decode data more
* than once.
*/
protected byte[] _binaryValue;
/*
/**********************************************************
/* Life-cycle
/**********************************************************
*/
public FromXmlParser(IOContext ctxt, int genericParserFeatures, int xmlFeatures,
ObjectCodec codec, XMLStreamReader xmlReader)
{
super(genericParserFeatures);
_xmlFeatures = xmlFeatures;
_ioContext = ctxt;
_objectCodec = codec;
_parsingContext = JsonReadContext.createRootContext(-1, -1);
// and thereby start a scope
_nextToken = JsonToken.START_OBJECT;
_xmlTokens = new XmlTokenStream(xmlReader, ctxt.getSourceReference());
}
@Override
public ObjectCodec getCodec() {
return _objectCodec;
}
@Override
public void setCodec(ObjectCodec c) {
_objectCodec = c;
}
/*
/**********************************************************
/* Extended API, configuration
/**********************************************************
*/
public FromXmlParser enable(Feature f) {
_xmlFeatures |= f.getMask();
return this;
}
public FromXmlParser disable(Feature f) {
_xmlFeatures &= ~f.getMask();
return this;
}
public final boolean isEnabled(Feature f) {
return (_xmlFeatures & f.getMask()) != 0;
}
public FromXmlParser configure(Feature f, boolean state) {
if (state) {
enable(f);
} else {
disable(f);
}
return this;
}
/*
/**********************************************************
/* Extended API, access to some internal components
/**********************************************************
*/
/**
* Method that allows application direct access to underlying
* Stax {@link XMLStreamWriter}. Note that use of writer is
* discouraged, and may interfere with processing of this writer;
* however, occasionally it may be necessary.
*
* Note: writer instance will always be of type
* {@link org.codehaus.stax2.XMLStreamWriter2} (including
* Typed Access API) so upcasts are safe.
*
* @since 1.7
*/
public XMLStreamReader getStaxReader() {
return _xmlTokens.getXmlReader();
}
/*
/**********************************************************
/* JsonParser impl
/**********************************************************
*/
/**
* Method that can be called to get the name associated with
* the current event.
*/
@Override
public String getCurrentName()
throws IOException, JsonParseException
{
// [JACKSON-395]: start markers require information from parent
if (_currToken == JsonToken.START_OBJECT || _currToken == JsonToken.START_ARRAY) {
JsonReadContext parent = _parsingContext.getParent();
return parent.getCurrentName();
}
return _parsingContext.getCurrentName();
}
@Override
public void close() throws IOException
{
if (!_closed) {
_closed = true;
try {
if (_ioContext.isResourceManaged() || isEnabled(JsonParser.Feature.AUTO_CLOSE_SOURCE)) {
_xmlTokens.closeCompletely();
} else {
_xmlTokens.close();
}
} finally {
// as per [JACKSON-324], do in finally block
// Also, internal buffer(s) can now be released as well
_releaseBuffers();
}
}
}
@Override
public boolean isClosed() { return _closed; }
@Override
public JsonReadContext getParsingContext()
{
return _parsingContext;
}
/**
* Method that return the starting location of the current
* token; that is, position of the first character from input
* that starts the current token.
*/
@Override
public JsonLocation getTokenLocation()
{
return _xmlTokens.getTokenLocation();
}
/**
* Method that returns location of the last processed character;
* usually for error reporting purposes
*/
@Override
public JsonLocation getCurrentLocation()
{
return _xmlTokens.getCurrentLocation();
}
/**
* Since xml representation can not really distinguish between array
* and object starts (both are represented with elements), this method
* is overridden and taken to mean that expecation is that the current
* start element is to mean 'start array', instead of default of
* 'start object'.
*/
@Override
public boolean isExpectedStartArrayToken() {
JsonToken t = _currToken;
if (t == JsonToken.START_OBJECT) {
_currToken = JsonToken.START_ARRAY;
// Ok: must replace current context with array as well
_parsingContext = _parsingContext.getParent();
_parsingContext = _parsingContext.createChildArrayContext(-1, -1);
// And just in case a field name was to be returned, wipe it
_nextToken = null;
return true;
}
return (t == JsonToken.START_ARRAY);
}
@Override
public JsonToken nextToken() throws IOException, JsonParseException
{
if (_nextToken != null) {
JsonToken t = _nextToken;
_currToken = t;
_nextToken = null;
switch (t) {
case START_OBJECT:
_parsingContext = _parsingContext.createChildObjectContext(-1, -1);
break;
case START_ARRAY:
_parsingContext = _parsingContext.createChildArrayContext(-1, -1);
break;
case END_OBJECT:
case END_ARRAY:
_parsingContext = _parsingContext.getParent();
break;
case FIELD_NAME:
_parsingContext.setCurrentName(_xmlTokens.getLocalName());
break;
default: // VALUE_STRING, VALUE_NULL
// should be fine as is?
}
return t;
}
int token = _xmlTokens.next();
/* Need to have a loop just because we may have to eat/convert
* a start-element that indicates an array element.
*/
while (token == XmlTokenStream.XML_START_ELEMENT) {
// If we thought we might get leaf, no such luck
if (_mayBeLeaf) {
// leave _mayBeLeaf set, as we start a new context
_nextToken = JsonToken.FIELD_NAME;
_parsingContext = _parsingContext.createChildObjectContext(-1, -1);
return (_currToken = JsonToken.START_OBJECT);
}
if (_parsingContext.inArray()) {
/* Yup: in array, so this element could be verified; but it won't be reported
* anyway, and we need to process following event.
*/
token = _xmlTokens.next();
_mayBeLeaf = true;
continue;
}
_parsingContext.setCurrentName(_xmlTokens.getLocalName());
_mayBeLeaf = true;
/* Ok: in array context we need to skip reporting field names. But what's the best way
* to find next token?
*
*/
return (_currToken = JsonToken.FIELD_NAME);
}
// Ok; beyond start element, what do we get?
switch (token) {
case XmlTokenStream.XML_END_ELEMENT:
// Simple, except that if this is a leaf, need to suppress end:
if (_mayBeLeaf) {
_mayBeLeaf = false;
return (_currToken = JsonToken.VALUE_NULL);
}
_currToken = _parsingContext.inArray() ? JsonToken.END_ARRAY : JsonToken.END_OBJECT;
_parsingContext = _parsingContext.getParent();
return _currToken;
case XmlTokenStream.XML_ATTRIBUTE_NAME:
// If there was a chance of leaf node, no more...
if (_mayBeLeaf) {
_mayBeLeaf = false;
_nextToken = JsonToken.FIELD_NAME;
_currText = _xmlTokens.getText();
_parsingContext = _parsingContext.createChildObjectContext(-1, -1);
return (_currToken = JsonToken.START_OBJECT);
}
_mayBeLeaf = false;
_parsingContext.setCurrentName(_xmlTokens.getLocalName());
return (_currToken = JsonToken.FIELD_NAME);
case XmlTokenStream.XML_ATTRIBUTE_VALUE:
_currText = _xmlTokens.getText();
return (_currToken = JsonToken.VALUE_STRING);
case XmlTokenStream.XML_TEXT:
_currText = _xmlTokens.getText();
if (_mayBeLeaf) {
_mayBeLeaf = false;
// Also: must skip following END_ELEMENT
_xmlTokens.skipEndElement();
return (_currToken = JsonToken.VALUE_STRING);
}
// If not a leaf, need to transform into property...
_parsingContext.setCurrentName(UNNAMED_TEXT_PROPERTY);
_nextToken = JsonToken.VALUE_STRING;
return (_currToken = JsonToken.FIELD_NAME);
case XmlTokenStream.XML_END:
return (_currToken = null);
}
// should never get here
_throwInternal();
return null;
}
/*
/**********************************************************
/* Public API, access to token information, text
/**********************************************************
*/
@Override
public String getText() throws IOException, JsonParseException
{
switch (_currToken) {
case FIELD_NAME:
return getCurrentName();
case VALUE_STRING:
return _currText;
}
return (_currToken == null) ? null : _currToken.asString();
}
@Override
public char[] getTextCharacters() throws IOException, JsonParseException {
String text = getText();
return (text == null) ? null : text.toCharArray();
}
@Override
public int getTextLength() throws IOException, JsonParseException {
String text = getText();
return (text == null) ? 0 : text.length();
}
@Override
public int getTextOffset() throws IOException, JsonParseException {
return 0;
}
/**
* XML input actually would offer access to character arrays; but since
* we must coalesce things it cannot really be exposed.
*/
@Override
public boolean hasTextCharacters()
{
return false;
}
/*
/**********************************************************
/* Public API, access to token information, binary
/**********************************************************
*/
@Override
public byte[] getBinaryValue(Base64Variant b64variant)
throws IOException, JsonParseException
{
if (_currToken != JsonToken.VALUE_STRING &&
(_currToken != JsonToken.VALUE_EMBEDDED_OBJECT || _binaryValue == null)) {
_reportError("Current token ("+_currToken+") not VALUE_STRING or VALUE_EMBEDDED_OBJECT, can not access as binary");
}
/* To ensure that we won't see inconsistent data, better clear up
* state...
*/
if (_binaryValue == null) {
try {
_binaryValue = _decodeBase64(b64variant);
} catch (IllegalArgumentException iae) {
throw _constructError("Failed to decode VALUE_STRING as base64 ("+b64variant+"): "+iae.getMessage());
}
}
return _binaryValue;
}
protected byte[] _decodeBase64(Base64Variant b64variant)
throws IOException, JsonParseException
{
ByteArrayBuilder builder = _getByteArrayBuilder();
final String str = getText();
int ptr = 0;
int len = str.length();
main_loop:
while (ptr < len) {
// first, we'll skip preceding white space, if any
char ch;
do {
ch = str.charAt(ptr++);
if (ptr >= len) {
break main_loop;
}
} while (ch <= INT_SPACE);
int bits = b64variant.decodeBase64Char(ch);
if (bits < 0) {
_reportInvalidBase64(b64variant, ch, 0, null);
}
int decodedData = bits;
// then second base64 char; can't get padding yet, nor ws
if (ptr >= len) {
_reportBase64EOF();
}
ch = str.charAt(ptr++);
bits = b64variant.decodeBase64Char(ch);
if (bits < 0) {
_reportInvalidBase64(b64variant, ch, 1, null);
}
decodedData = (decodedData << 6) | bits;
// third base64 char; can be padding, but not ws
if (ptr >= len) {
_reportBase64EOF();
}
ch = str.charAt(ptr++);
bits = b64variant.decodeBase64Char(ch);
// First branch: can get padding (-> 1 byte)
if (bits < 0) {
if (bits != Base64Variant.BASE64_VALUE_PADDING) {
_reportInvalidBase64(b64variant, ch, 2, null);
}
// Ok, must get padding
if (ptr >= len) {
_reportBase64EOF();
}
ch = str.charAt(ptr++);
if (!b64variant.usesPaddingChar(ch)) {
_reportInvalidBase64(b64variant, ch, 3, "expected padding character '"+b64variant.getPaddingChar()+"'");
}
// Got 12 bits, only need 8, need to shift
decodedData >>= 4;
builder.append(decodedData);
continue;
}
// Nope, 2 or 3 bytes
decodedData = (decodedData << 6) | bits;
// fourth and last base64 char; can be padding, but not ws
if (ptr >= len) {
_reportBase64EOF();
}
ch = str.charAt(ptr++);
bits = b64variant.decodeBase64Char(ch);
if (bits < 0) {
if (bits != Base64Variant.BASE64_VALUE_PADDING) {
_reportInvalidBase64(b64variant, ch, 3, null);
}
decodedData >>= 2;
builder.appendTwoBytes(decodedData);
} else {
// otherwise, our triple is now complete
decodedData = (decodedData << 6) | bits;
builder.appendThreeBytes(decodedData);
}
}
return builder.toByteArray();
}
/**
* @param bindex Relative index within base64 character unit; between 0
* and 3 (as unit has exactly 4 characters)
*/
protected void _reportInvalidBase64(Base64Variant b64variant, char ch, int bindex, String msg)
throws JsonParseException
{
String base;
if (ch <= INT_SPACE) {
base = "Illegal white space character (code 0x"+Integer.toHexString(ch)+") as character #"+(bindex+1)+" of 4-char base64 unit: can only used between units";
} else if (b64variant.usesPaddingChar(ch)) {
base = "Unexpected padding character ('"+b64variant.getPaddingChar()+"') as character #"+(bindex+1)+" of 4-char base64 unit: padding only legal as 3rd or 4th character";
} else if (!Character.isDefined(ch) || Character.isISOControl(ch)) {
// Not sure if we can really get here... ? (most illegal xml chars are caught at lower level)
base = "Illegal character (code 0x"+Integer.toHexString(ch)+") in base64 content";
} else {
base = "Illegal character '"+ch+"' (code 0x"+Integer.toHexString(ch)+") in base64 content";
}
if (msg != null) {
base = base + ": " + msg;
}
throw new JsonParseException(base, JsonLocation.NA);
}
protected void _reportBase64EOF()
throws JsonParseException
{
throw new JsonParseException("Unexpected end-of-String when base64 content", JsonLocation.NA);
}
/*
/**********************************************************
/* Numeric accessors
/**********************************************************
*/
@Override
public BigInteger getBigIntegerValue() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return null;
}
@Override
public BigDecimal getDecimalValue() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return null;
}
@Override
public double getDoubleValue() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return 0;
}
@Override
public float getFloatValue() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return 0;
}
@Override
public int getIntValue() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return 0;
}
@Override
public long getLongValue() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return 0;
}
@Override
public NumberType getNumberType() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return null;
}
@Override
public Number getNumberValue() throws IOException, JsonParseException
{
// TODO Auto-generated method stub
return null;
}
/*
/**********************************************************
/* Abstract method impls for stuff from JsonParser
/**********************************************************
*/
/**
* Method called when an EOF is encountered between tokens.
* If so, it may be a legitimate EOF, but only iff there
* is no open non-root context.
*/
@Override
protected void _handleEOF() throws JsonParseException
{
if (!_parsingContext.inRoot()) {
_reportInvalidEOF(": expected close marker for "+_parsingContext.getTypeDesc()+" (from "+_parsingContext.getStartLocation(_ioContext.getSourceReference())+")");
}
}
/*
/**********************************************************
/* Internal methods
/**********************************************************
*/
/**
* Method called to release internal buffers owned by the base
* parser.
*/
protected void _releaseBuffers() throws IOException
{
// anything we can/must release? Underlying parser should do all of it, for now?
}
protected ByteArrayBuilder _getByteArrayBuilder()
{
if (_byteArrayBuilder == null) {
_byteArrayBuilder = new ByteArrayBuilder();
} else {
_byteArrayBuilder.reset();
}
return _byteArrayBuilder;
}
}