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package com.fasterxml.jackson.dataformat.xml.deser;

import java.io.IOException;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Set;

import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamWriter;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.core.base.ParserMinimalBase;
import com.fasterxml.jackson.core.io.IOContext;
import com.fasterxml.jackson.core.util.ByteArrayBuilder;
import com.fasterxml.jackson.dataformat.xml.PackageVersion;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;

/**
 * {@link JsonParser} implementation that exposes XML structure as
 * set of JSON events that can be used for data binding.
 */
public class FromXmlParser
    extends ParserMinimalBase
{
    /**
     * The default name placeholder for XML text segments is empty
     * String ("").
     */
    public final static String DEFAULT_UNNAMED_TEXT_PROPERTY = "";
    
    /**
     * 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.
     *

* Name used for pseudo-property used for returning XML Text value (which does * not have actual element name to use). Defaults to empty String, but * may be changed for interoperability reasons: JAXB, for example, uses * "value" as name. * * @since 2.1 */ protected String _cfgNameForTextElement = DEFAULT_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 XmlReadContext _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; protected Set _namesToWrap; /* /********************************************************** /* 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 = XmlReadContext.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; } /** * @since 2.1 */ public void setXMLTextElementName(String name) { _cfgNameForTextElement = name; } /** * XML format does require support from custom {@link ObjectCodec} * (that is, {@link XmlMapper}), so need to return true here. * * @return True since XML format does require support from codec */ @Override public boolean requiresCustomCodec() { return false; } /* /********************************************************** /* 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. */ public XMLStreamReader getStaxReader() { return _xmlTokens.getXmlReader(); } /* /********************************************************** /* Internal API /********************************************************** */ /** * Method that may be called to indicate that specified names * (only local parts retained currently: this may be changed in * future) should be considered "auto-wrapping", meaning that * they will be doubled to contain two opening elements, two * matching closing elements. This is needed for supporting * handling of so-called "unwrapped" array types, something * XML mappings like JAXB often use. *

* NOTE: this method is considered part of internal implementation * interface, and it is NOT guaranteed to remain unchanged * between minor versions (it is however expected not to change in * patch versions). So if you have to use it, be prepared for * possible additional work. * * @since 2.1 */ public void addVirtualWrapping(Set namesToWrap) { /* 17-Sep-2012, tatu: Not 100% sure why, but this is necessary to avoid * problems with Lists-in-Lists properties */ String name = _xmlTokens.getLocalName(); if (name != null && namesToWrap.contains(name)) { _xmlTokens.repeatStartElement(); } _namesToWrap = namesToWrap; _parsingContext.setNamesToWrap(namesToWrap); } /* /********************************************************** /* 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 String name; if (_currToken == JsonToken.START_OBJECT || _currToken == JsonToken.START_ARRAY) { XmlReadContext parent = _parsingContext.getParent(); name = parent.getCurrentName(); } else { name = _parsingContext.getCurrentName(); } // sanity check if (name == null) { throw new IllegalStateException("Missing name, in state: "+_currToken); } return name; } @Override public void overrideCurrentName(String name) { // Simple, but need to look for START_OBJECT/ARRAY's "off-by-one" thing: XmlReadContext ctxt = _parsingContext; if (_currToken == JsonToken.START_OBJECT || _currToken == JsonToken.START_ARRAY) { ctxt = ctxt.getParent(); } ctxt.setCurrentName(name); } @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 XmlReadContext 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.convertToArray(); //System.out.println(" isExpectedArrayStart: OBJ->Array, wraps now: "+_parsingContext.getNamesToWrap()); // And just in case a field name was to be returned, wipe it _nextToken = null; // and last thing, [Issue#33], better ignore attributes _xmlTokens.skipAttributes(); return true; } //System.out.println(" isExpectedArrayStart?: t="+t); return (t == JsonToken.START_ARRAY); } // DEBUGGING /* @Override public JsonToken nextToken() throws IOException, JsonParseException { JsonToken t = nextToken0(); if (t != null) { switch (t) { case FIELD_NAME: System.out.println("JsonToken: FIELD_NAME '"+_parsingContext.getCurrentName()+"'"); break; case VALUE_STRING: System.out.println("JsonToken: VALUE_STRING '"+getText()+"'"); break; default: System.out.println("JsonToken: "+t); } } return t; } */ @Override public JsonToken nextToken() throws IOException, JsonParseException { _binaryValue = null; // to fix [Issue-29] 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(); _namesToWrap = _parsingContext.getNamesToWrap(); 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; } String name = _xmlTokens.getLocalName(); _parsingContext.setCurrentName(name); /* Ok: virtual wrapping can be done by simply repeating * current START_ELEMENT. Couple of ways to do it; but * start by making _xmlTokens replay the thing... */ if (_namesToWrap != null && _namesToWrap.contains(name)) { _xmlTokens.repeatStartElement(); } _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(); _namesToWrap = _parsingContext.getNamesToWrap(); 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); } _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(); /* One more refinement (pronunced like "hack") is that if * we had an empty String (or all white space), and we are * deserializing an array, we better just hide the text * altogether. */ if (_parsingContext.inArray()) { if (_isEmpty(_currText)) { _currToken = JsonToken.END_ARRAY; _parsingContext = _parsingContext.getParent(); _namesToWrap = _parsingContext.getNamesToWrap(); return _currToken; } } return (_currToken = JsonToken.VALUE_STRING); } // If not a leaf, need to transform into property... _parsingContext.setCurrentName(_cfgNameForTextElement); _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 { if (_currToken == null) { return null; } switch (_currToken) { case FIELD_NAME: return getCurrentName(); case VALUE_STRING: return _currText; default: return _currToken.asString(); } } // @since 2.1 @Override public final String getValueAsString() throws IOException, JsonParseException { return getValueAsString(null); } @Override public String getValueAsString(String defValue) throws IOException, JsonParseException { JsonToken t = _currToken; if (t == null) { return null; } switch (t) { case FIELD_NAME: return getCurrentName(); case VALUE_STRING: return _currText; case START_OBJECT: // the interesting case; may be able to convert certain kinds of // elements (specifically, ones with attributes, CDATA only content) // into VALUE_STRING { String str = _xmlTokens.convertToString(); if (str != null) { // need to convert token, as well as "undo" START_OBJECT // note: Should NOT update context, because we will still be getting // matching END_OBJECT, which will undo contexts properly _parsingContext = _parsingContext.getParent(); _namesToWrap = _parsingContext.getNamesToWrap(); _currToken = JsonToken.VALUE_STRING; _nextToken = null; /* One more thing: must explicitly skip the END_OBJECT that * would follow. */ _xmlTokens.skipEndElement(); return (_currText = str); } } return null; default: if (_currToken.isScalarValue()) { return _currToken.asString(); } } return defValue; } @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 Object getEmbeddedObject() throws IOException, JsonParseException { // no way to embed POJOs for now... return null; } @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; } @SuppressWarnings("resource") protected byte[] _decodeBase64(Base64Variant b64variant) throws IOException, JsonParseException { ByteArrayBuilder builder = _getByteArrayBuilder(); final String str = getText(); _decodeBase64(str, builder, b64variant); return builder.toByteArray(); } /* /********************************************************** /* 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; } protected boolean _isEmpty(String str) { int len = (str == null) ? 0 : str.length(); if (len > 0) { for (int i = 0; i < len; ++i) { if (str.charAt(i) > ' ') { return false; } } } return true; } @Override public Version version() { return PackageVersion.VERSION; } }





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