src/main/java/com/fasterxml/jackson/core/JsonStreamContext.java - platform/external/jackson-core - Gitiles

 /* Jackson JSON-processor.
  *
  * Copyright (c) 2007- Tatu Saloranta, tatu.saloranta@iki.fi
  */

 package com.fasterxml.jackson.core;

 import com.fasterxml.jackson.core.io.CharTypes;

 /**
  * Shared base class for streaming processing contexts used during
  * reading and writing of Json content using Streaming API.
  * This context is also exposed to applications:
  * context object can be used by applications to get an idea of
  * relative position of the parser/generator within json content
  * being processed. This allows for some contextual processing: for
  * example, output within Array context can differ from that of
  * Object context.
  */
 public abstract class JsonStreamContext
 {
     // // // Type constants used internally

     protected final static int TYPE_ROOT = 0;
     protected final static int TYPE_ARRAY = 1;
     protected final static int TYPE_OBJECT = 2;

     protected int _type;

     /**
      * Index of the currently processed entry. Starts with -1 to signal
      * that no entries have been started, and gets advanced each
      * time a new entry is started, either by encountering an expected
      * separator, or with new values if no separators are expected
      * (the case for root context).
      */
     protected int _index;

     /*
     /**********************************************************
     /* Life-cycle
     /**********************************************************
      */

     protected JsonStreamContext() { }

     /**
      * Copy constructor used by sub-classes for creating copies for
      * buffering.
      *
      * @since 2.9
      */
     protected JsonStreamContext(JsonStreamContext base) {
         _type = base._type;
         _index = base._index;
     }

     /**
      * @since 2.9
      */
     protected JsonStreamContext(int type, int index) {
         _type = type;
         _index = index;
     }

     /*
     /**********************************************************
     /* Public API, accessors
     /**********************************************************
      */

     /**
      * Accessor for finding parent context of this context; will
      * return null for root context.
      */
     public abstract JsonStreamContext getParent();

     /**
      * Method that returns true if this context is an Array context;
      * that is, content is being read from or written to a Json Array.
      */
     public final boolean inArray() { return _type == TYPE_ARRAY; }

     /**
      * Method that returns true if this context is a Root context;
      * that is, content is being read from or written to without
      * enclosing array or object structure.
      */
     public final boolean inRoot() { return _type == TYPE_ROOT; }

     /**
      * Method that returns true if this context is an Object context;
      * that is, content is being read from or written to a Json Object.
      */
     public final boolean inObject() { return _type == TYPE_OBJECT; }

     /**
      * Method for accessing simple type description of current context;
      * either ROOT (for root-level values), OBJECT (for field names and
      * values of JSON Objects) or ARRAY (for values of JSON Arrays)
      *
      * @deprecated Since 2.8 use {@link #typeDesc} instead
      */
     @Deprecated // since 2.8
     public final String getTypeDesc() {
         switch (_type) {
         case TYPE_ROOT: return "ROOT";
         case TYPE_ARRAY: return "ARRAY";
         case TYPE_OBJECT: return "OBJECT";
         }
         return "?";
     }

     /**
      * @since 2.8
      */
     public String typeDesc() {
         switch (_type) {
         case TYPE_ROOT: return "root";
         case TYPE_ARRAY: return "Array";
         case TYPE_OBJECT: return "Object";
         }
         return "?";
     }

     /**
      * @return Number of entries that are complete and started.
      */
     public final int getEntryCount() { return _index + 1; }

     /**
      * @return Index of the currently processed entry, if any
      */
     public final int getCurrentIndex() { return (_index < 0) ? 0 : _index; }

     /**
      * Method that may be called to verify whether this context has valid index:
      * will return `false` before the first entry of Object context or before
      * first element of Array context; otherwise returns `true`.
      *
      * @since 2.9
      */
     public boolean hasCurrentIndex() { return _index >= 0; }

     /**
      * Method that may be called to check if this context is either:
      *<ul>
      * <li>Object, with at least one entry written (partially or completely)
      *  </li>
      * <li>Array, with at least one entry written (partially or completely)
      *  </li>
      *</ul>
      * and if so, return `true`; otherwise return `false`. Latter case includes
      * Root context (always), and Object/Array contexts before any entries/elements
      * have been read or written.
      *<p>
      * Method is mostly used to determine whether this context should be used for
      * constructing {@link JsonPointer}
      *
      * @since 2.9
      */
     public boolean hasPathSegment() {
         if (_type == TYPE_OBJECT) {
             return hasCurrentName();
         } else if (_type == TYPE_ARRAY) {
             return hasCurrentIndex();
         }
         return false;
     }

     /**
      * Method for accessing name associated with the current location.
      * Non-null for <code>FIELD_NAME</code> and value events that directly
      * follow field names; null for root level and array values.
      */
     public abstract String getCurrentName();

     /**
      * @since 2.9
      */
     public boolean hasCurrentName() { return getCurrentName() != null; }

     /**
      * Method for accessing currently active value being used by data-binding
      * (as the source of streaming data to write, or destination of data being
      * read), at this level in hierarchy.
      *<p>
      * Note that "current value" is NOT populated (or used) by Streaming parser or generator;
      * it is only used by higher-level data-binding functionality.
      * The reason it is included here is that it can be stored and accessed hierarchically,
      * and gets passed through data-binding.
      *
      * @return Currently active value, if one has been assigned.
      *
      * @since 2.5
      */
     public Object getCurrentValue() {
         return null;
     }

     /**
      * Method to call to pass value to be returned via {@link #getCurrentValue}; typically
      * called indirectly through {@link JsonParser#setCurrentValue}
      * or {@link JsonGenerator#setCurrentValue}).
      *
      * @since 2.5
      */
     public void setCurrentValue(Object v) { }

     /**
      * Factory method for constructing a {@link JsonPointer} that points to the current
      * location within the stream that this context is for, excluding information about
      * "root context" (only relevant for multi-root-value cases)
      *
      * @since 2.9
      */
     public JsonPointer pathAsPointer() {
         return JsonPointer.forPath(this, false);
     }

     /**
      * Factory method for constructing a {@link JsonPointer} that points to the current
      * location within the stream that this context is for, optionally including
      * "root value index"
      *
      * @param includeRoot Whether root-value offset is included as the first segment or not;
      *
      * @since 2.9
      */
     public JsonPointer pathAsPointer(boolean includeRoot) {
         return JsonPointer.forPath(this, includeRoot);
     }

     /**
      * Optional method that may be used to access starting location of this context:
      * for example, in case of JSON `Object` context, offset at which `[` token was
      * read or written. Often used for error reporting purposes.
      * Implementations that do not keep track of such location are expected to return
      * {@link JsonLocation#NA}; this is what the default implementation does.
      *
      * @return Location pointing to the point where the context
      *   start marker was found (or written); never `null`.
      *<p>
      * NOTE: demoted from <code>JsonReadContext</code> in 2.9, to allow use for
      * "non-standard" read contexts.
      *
      * @since 2.9
      */
     public JsonLocation getStartLocation(Object srcRef) {
         return JsonLocation.NA;
     }

     /**
      * Overridden to provide developer readable "JsonPath" representation
      * of the context.
      *
      * @since 2.9
      */
     @Override
     public String toString() {
         StringBuilder sb = new StringBuilder(64);
         switch (_type) {
         case TYPE_ROOT:
             sb.append("/");
             break;
         case TYPE_ARRAY:
             sb.append('[');
             sb.append(getCurrentIndex());
             sb.append(']');
             break;
         case TYPE_OBJECT:
         default:
             sb.append('{');
             String currentName = getCurrentName();
             if (currentName != null) {
                 sb.append('"');
                 CharTypes.appendQuoted(sb, currentName);
                 sb.append('"');
             } else {
                 sb.append('?');
             }
             sb.append('}');
             break;
         }
         return sb.toString();
     }
 }
	/* Jackson JSON-processor.
	*
	* Copyright (c) 2007- Tatu Saloranta, tatu.saloranta@iki.fi
	*/

	package com.fasterxml.jackson.core;

	import com.fasterxml.jackson.core.io.CharTypes;

	/**
	* Shared base class for streaming processing contexts used during
	* reading and writing of Json content using Streaming API.
	* This context is also exposed to applications:
	* context object can be used by applications to get an idea of
	* relative position of the parser/generator within json content
	* being processed. This allows for some contextual processing: for
	* example, output within Array context can differ from that of
	* Object context.
	*/
	public abstract class JsonStreamContext
	{
	// // // Type constants used internally

	protected final static int TYPE_ROOT = 0;
	protected final static int TYPE_ARRAY = 1;
	protected final static int TYPE_OBJECT = 2;

	protected int _type;

	/**
	* Index of the currently processed entry. Starts with -1 to signal
	* that no entries have been started, and gets advanced each
	* time a new entry is started, either by encountering an expected
	* separator, or with new values if no separators are expected
	* (the case for root context).
	*/
	protected int _index;

	/*
	/**********************************************************
	/* Life-cycle
	/**********************************************************
	*/

	protected JsonStreamContext() { }

	/**
	* Copy constructor used by sub-classes for creating copies for
	* buffering.
	*
	* @since 2.9
	*/
	protected JsonStreamContext(JsonStreamContext base) {
	_type = base._type;
	_index = base._index;
	}

	/**
	* @since 2.9
	*/
	protected JsonStreamContext(int type, int index) {
	_type = type;
	_index = index;
	}

	/*
	/**********************************************************
	/* Public API, accessors
	/**********************************************************
	*/

	/**
	* Accessor for finding parent context of this context; will
	* return null for root context.
	*/
	public abstract JsonStreamContext getParent();

	/**
	* Method that returns true if this context is an Array context;
	* that is, content is being read from or written to a Json Array.
	*/
	public final boolean inArray() { return _type == TYPE_ARRAY; }

	/**
	* Method that returns true if this context is a Root context;
	* that is, content is being read from or written to without
	* enclosing array or object structure.
	*/
	public final boolean inRoot() { return _type == TYPE_ROOT; }

	/**
	* Method that returns true if this context is an Object context;
	* that is, content is being read from or written to a Json Object.
	*/
	public final boolean inObject() { return _type == TYPE_OBJECT; }

	/**
	* Method for accessing simple type description of current context;
	* either ROOT (for root-level values), OBJECT (for field names and
	* values of JSON Objects) or ARRAY (for values of JSON Arrays)
	*
	* @deprecated Since 2.8 use {@link #typeDesc} instead
	*/
	@Deprecated // since 2.8
	public final String getTypeDesc() {
	switch (_type) {
	case TYPE_ROOT: return "ROOT";
	case TYPE_ARRAY: return "ARRAY";
	case TYPE_OBJECT: return "OBJECT";
	}
	return "?";
	}

	/**
	* @since 2.8
	*/
	public String typeDesc() {
	switch (_type) {
	case TYPE_ROOT: return "root";
	case TYPE_ARRAY: return "Array";
	case TYPE_OBJECT: return "Object";
	}
	return "?";
	}

	/**
	* @return Number of entries that are complete and started.
	*/
	public final int getEntryCount() { return _index + 1; }

	/**
	* @return Index of the currently processed entry, if any
	*/
	public final int getCurrentIndex() { return (_index < 0) ? 0 : _index; }

	/**
	* Method that may be called to verify whether this context has valid index:
	* will return `false` before the first entry of Object context or before
	* first element of Array context; otherwise returns `true`.
	*
	* @since 2.9
	*/
	public boolean hasCurrentIndex() { return _index >= 0; }

	/**
	* Method that may be called to check if this context is either:
	*<ul>
	* <li>Object, with at least one entry written (partially or completely)
	* </li>
	* <li>Array, with at least one entry written (partially or completely)
	* </li>
	*</ul>
	* and if so, return `true`; otherwise return `false`. Latter case includes
	* Root context (always), and Object/Array contexts before any entries/elements
	* have been read or written.
	*<p>
	* Method is mostly used to determine whether this context should be used for
	* constructing {@link JsonPointer}
	*
	* @since 2.9
	*/
	public boolean hasPathSegment() {
	if (_type == TYPE_OBJECT) {
	return hasCurrentName();
	} else if (_type == TYPE_ARRAY) {
	return hasCurrentIndex();
	}
	return false;
	}

	/**
	* Method for accessing name associated with the current location.
	* Non-null for <code>FIELD_NAME</code> and value events that directly
	* follow field names; null for root level and array values.
	*/
	public abstract String getCurrentName();

	/**
	* @since 2.9
	*/
	public boolean hasCurrentName() { return getCurrentName() != null; }

	/**
	* Method for accessing currently active value being used by data-binding
	* (as the source of streaming data to write, or destination of data being
	* read), at this level in hierarchy.
	*<p>
	* Note that "current value" is NOT populated (or used) by Streaming parser or generator;
	* it is only used by higher-level data-binding functionality.
	* The reason it is included here is that it can be stored and accessed hierarchically,
	* and gets passed through data-binding.
	*
	* @return Currently active value, if one has been assigned.
	*
	* @since 2.5
	*/
	public Object getCurrentValue() {
	return null;
	}

	/**
	* Method to call to pass value to be returned via {@link #getCurrentValue}; typically
	* called indirectly through {@link JsonParser#setCurrentValue}
	* or {@link JsonGenerator#setCurrentValue}).
	*
	* @since 2.5
	*/
	public void setCurrentValue(Object v) { }

	/**
	* Factory method for constructing a {@link JsonPointer} that points to the current
	* location within the stream that this context is for, excluding information about
	* "root context" (only relevant for multi-root-value cases)
	*
	* @since 2.9
	*/
	public JsonPointer pathAsPointer() {
	return JsonPointer.forPath(this, false);
	}

	/**
	* Factory method for constructing a {@link JsonPointer} that points to the current
	* location within the stream that this context is for, optionally including
	* "root value index"
	*
	* @param includeRoot Whether root-value offset is included as the first segment or not;
	*
	* @since 2.9
	*/
	public JsonPointer pathAsPointer(boolean includeRoot) {
	return JsonPointer.forPath(this, includeRoot);
	}

	/**
	* Optional method that may be used to access starting location of this context:
	* for example, in case of JSON `Object` context, offset at which `[` token was
	* read or written. Often used for error reporting purposes.
	* Implementations that do not keep track of such location are expected to return
	* {@link JsonLocation#NA}; this is what the default implementation does.
	*
	* @return Location pointing to the point where the context
	* start marker was found (or written); never `null`.
	*<p>
	* NOTE: demoted from <code>JsonReadContext</code> in 2.9, to allow use for
	* "non-standard" read contexts.
	*
	* @since 2.9
	*/
	public JsonLocation getStartLocation(Object srcRef) {
	return JsonLocation.NA;
	}

	/**
	* Overridden to provide developer readable "JsonPath" representation
	* of the context.
	*
	* @since 2.9
	*/
	@Override
	public String toString() {
	StringBuilder sb = new StringBuilder(64);
	switch (_type) {
	case TYPE_ROOT:
	sb.append("/");
	break;
	case TYPE_ARRAY:
	sb.append('[');
	sb.append(getCurrentIndex());
	sb.append(']');
	break;
	case TYPE_OBJECT:
	default:
	sb.append('{');
	String currentName = getCurrentName();
	if (currentName != null) {
	sb.append('"');
	CharTypes.appendQuoted(sb, currentName);
	sb.append('"');
	} else {
	sb.append('?');
	}
	sb.append('}');
	break;
	}
	return sb.toString();
	}
	}