com.eclipsesource.json.JsonHandler Maven / Gradle / Ivy
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*
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*
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*
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package com.eclipsesource.json;
/**
* A handler for parser events. Instances of this class can be given to a {@link JsonParser}. The
* parser will then call the methods of the given handler while reading the input.
*
* The default implementations of these methods do nothing. Subclasses may override only those
* methods they are interested in. They can use getLocation() to access the current
* character position of the parser at any point. The start* methods will be called
* while the location points to the first character of the parsed element. The end*
* methods will be called while the location points to the character position that directly follows
* the last character of the parsed element. Example:
*
*
*
* ["lorem ipsum"]
* ^ ^
* startString endString
*
*
* Subclasses that build an object representation of the parsed JSON can return arbitrary handler
* objects for JSON arrays and JSON objects in {@link #startArray()} and {@link #startObject()}.
* These handler objects will then be provided in all subsequent parser events for this particular
* array or object. They can be used to keep track the elements of a JSON array or object.
*
*
* @param
* The type of handlers used for JSON arrays
* @param
* The type of handlers used for JSON objects
* @see JsonParser
*/
public abstract class JsonHandler {
JsonParser parser;
/**
* Returns the current parser location.
*
* @return the current parser location
*/
protected Location getLocation() {
return parser.getLocation();
}
/**
* Indicates the beginning of a null literal in the JSON input. This method will be
* called when reading the first character of the literal.
*/
public void startNull() {
}
/**
* Indicates the end of a null literal in the JSON input. This method will be called
* after reading the last character of the literal.
*/
public void endNull() {
}
/**
* Indicates the beginning of a boolean literal (true or false) in the
* JSON input. This method will be called when reading the first character of the literal.
*/
public void startBoolean() {
}
/**
* Indicates the end of a boolean literal (true or false) in the JSON
* input. This method will be called after reading the last character of the literal.
*
* @param value
* the parsed boolean value
*/
public void endBoolean(boolean value) {
}
/**
* Indicates the beginning of a string in the JSON input. This method will be called when reading
* the opening double quote character ('"').
*/
public void startString() {
}
/**
* Indicates the end of a string in the JSON input. This method will be called after reading the
* closing double quote character ('"').
*
* @param string
* the parsed string
*/
public void endString(String string) {
}
/**
* Indicates the beginning of a number in the JSON input. This method will be called when reading
* the first character of the number.
*/
public void startNumber() {
}
/**
* Indicates the end of a number in the JSON input. This method will be called after reading the
* last character of the number.
*
* @param string
* the parsed number string
*/
public void endNumber(String string) {
}
/**
* Indicates the beginning of an array in the JSON input. This method will be called when reading
* the opening square bracket character ('[').
*
* This method may return an object to handle subsequent parser events for this array. This array
* handler will then be provided in all calls to {@link #startArrayValue(Object)
* startArrayValue()}, {@link #endArrayValue(Object) endArrayValue()}, and
* {@link #endArray(Object) endArray()} for this array.
*
*
* @return a handler for this array, or null if not needed
*/
public A startArray() {
return null;
}
/**
* Indicates the end of an array in the JSON input. This method will be called after reading the
* closing square bracket character (']').
*
* @param array
* the array handler returned from {@link #startArray()}, or null if not
* provided
*/
public void endArray(A array) {
}
/**
* Indicates the beginning of an array element in the JSON input. This method will be called when
* reading the first character of the element, just before the call to the start
* method for the specific element type ({@link #startString()}, {@link #startNumber()}, etc.).
*
* @param array
* the array handler returned from {@link #startArray()}, or null if not
* provided
*/
public void startArrayValue(A array) {
}
/**
* Indicates the end of an array element in the JSON input. This method will be called after
* reading the last character of the element value, just after the end method for the
* specific element type (like {@link #endString(String) endString()}, {@link #endNumber(String)
* endNumber()}, etc.).
*
* @param array
* the array handler returned from {@link #startArray()}, or null if not
* provided
*/
public void endArrayValue(A array) {
}
/**
* Indicates the beginning of an object in the JSON input. This method will be called when reading
* the opening curly bracket character ('{').
*
* This method may return an object to handle subsequent parser events for this object. This
* object handler will be provided in all calls to {@link #startObjectName(Object)
* startObjectName()}, {@link #endObjectName(Object, String) endObjectName()},
* {@link #startObjectValue(Object, String) startObjectValue()},
* {@link #endObjectValue(Object, String) endObjectValue()}, and {@link #endObject(Object)
* endObject()} for this object.
*
*
* @return a handler for this object, or null if not needed
*/
public O startObject() {
return null;
}
/**
* Indicates the end of an object in the JSON input. This method will be called after reading the
* closing curly bracket character ('}').
*
* @param object
* the object handler returned from {@link #startObject()}, or null if not provided
*/
public void endObject(O object) {
}
/**
* Indicates the beginning of the name of an object member in the JSON input. This method will be
* called when reading the opening quote character ('"') of the member name.
*
* @param object
* the object handler returned from {@link #startObject()}, or null if not
* provided
*/
public void startObjectName(O object) {
}
/**
* Indicates the end of an object member name in the JSON input. This method will be called after
* reading the closing quote character ('"') of the member name.
*
* @param object
* the object handler returned from {@link #startObject()}, or null if not provided
* @param name
* the parsed member name
*/
public void endObjectName(O object, String name) {
}
/**
* Indicates the beginning of the name of an object member in the JSON input. This method will be
* called when reading the opening quote character ('"') of the member name.
*
* @param object
* the object handler returned from {@link #startObject()}, or null if not
* provided
* @param name
* the member name
*/
public void startObjectValue(O object, String name) {
}
/**
* Indicates the end of an object member value in the JSON input. This method will be called after
* reading the last character of the member value, just after the end method for the
* specific member type (like {@link #endString(String) endString()}, {@link #endNumber(String)
* endNumber()}, etc.).
*
* @param object
* the object handler returned from {@link #startObject()}, or null if not provided
* @param name
* the parsed member name
*/
public void endObjectValue(O object, String name) {
}
}