package com.imaginea.mongodb.utils;
import com.mongodb.DBObject;
import com.mongodb.util.JSONCallback;
import com.mongodb.util.JSONParseException;
import org.bson.BSONCallback;
import java.util.Stack;
/**
* Created with IntelliJ IDEA.
* Author: Srinath Anantha
*/
public class JSON extends com.mongodb.util.JSON {
/**
* Parses a JSON string representing a JSON value
*
* @param s the string to parse
* @return the object
*/
public static Object parse(String s) {
return parse(s, null);
}
/**
* Parses a JSON string representing a JSON value
*
* @param s the string to parse
* @return the object
*/
public static Object parse(String s, BSONCallback c) {
if (s == null || (s = s.trim()).equals("")) {
return null;
}
JSONParser p = new JSONParser(s, c);
return p.parse();
}
}
/**
* Parser for MongoDB objects.
* <p/>
* Supports all types described at www.json.org and mongoDB functions, except for
* numbers with "e" or "E" in them.
*/
class JSONParser {
private String s;
private int pos = 0;
private BSONCallback _callback;
/**
* Create a new parser.
*/
public JSONParser(String s) {
this(s, null);
}
/**
* Create a new parser.
*/
public JSONParser(String s, BSONCallback callback) {
this.s = s;
_callback = (callback == null) ? new JSONCallback() : callback;
}
/**
* Parse an unknown type.
*
* @return Object the next item
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
public Object parse() {
return parse(null);
}
/**
* Parse an unknown type.
*
* @return Object the next item
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
protected Object parse(String name) {
Object value = null;
char current = get();
switch (current) {
// null
case 'n':
read('n');
read('u');
read('l');
read('l');
value = null;
break;
// NaN
case 'N':
read('N');
read('a');
read('N');
value = Double.NaN;
break;
// true
case 't':
read('t');
read('r');
read('u');
read('e');
value = true;
break;
// false
case 'f':
read('f');
current = get();
switch (current) {
case 'a':
read('a');
read('l');
read('s');
read('e');
value = false;
break;
case 'u':
read('u');
read('n');
read('c');
read('t');
read('i');
read('o');
read('n');
StringBuilder funcStr = new StringBuilder("function");
char currentCharacter = get();
funcStr.append(" ");
while (currentCharacter != '{' && pos < s.length()) {
funcStr.append(currentCharacter);
currentCharacter = s.charAt(++pos);
}
value = parseFunction();
value = funcStr.append(value).toString();
break;
}
break;
// string
case '\'':
case '\"':
value = parseString(true);
break;
// number
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
case '+':
case '-':
value = parseNumber();
break;
// array
case '[':
value = parseArray(name);
break;
// object
case '{':
value = parseObject(name);
break;
default:
throw new JSONParseException(s, pos);
}
return value;
}
/**
* Parses an object for the form <i>{}</i> and <i>{ members }</i>.
*
* @return DBObject the next object
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
public Object parseObject() {
return parseObject(null);
}
/**
* Parses an object for the form <i>{}</i> and <i>{ members }</i>.
*
* @return DBObject the next object
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
protected Object parseObject(String name) {
if (name != null) {
_callback.objectStart(name);
} else {
_callback.objectStart();
}
read('{');
char current = get();
while (get() != '}') {
String key = parseString(false);
read(':');
Object value = parse(key);
doCallback(key, value);
if ((current = get()) == ',') {
read(',');
} else {
break;
}
}
read('}');
return _callback.objectDone();
}
protected void doCallback(String name, Object value) {
if (value == null) {
_callback.gotNull(name);
} else if (value instanceof String) {
_callback.gotString(name, (String) value);
} else if (value instanceof Boolean) {
_callback.gotBoolean(name, (Boolean) value);
} else if (value instanceof Integer) {
_callback.gotInt(name, (Integer) value);
} else if (value instanceof Long) {
_callback.gotLong(name, (Long) value);
} else if (value instanceof Double) {
_callback.gotDouble(name, (Double) value);
}
}
/**
* Read the current character, making sure that it is the expected character.
* Advances the pointer to the next character.
*
* @param ch the character expected
* @throws com.mongodb.util.JSONParseException
* if the current character does not match the given character
*/
public void read(char ch) {
if (!check(ch)) {
throw new JSONParseException(s, pos);
}
pos++;
}
public char read() {
if (pos >= s.length()) {
throw new IllegalStateException("string done");
}
return s.charAt(pos++);
}
/**
* Read the current character, making sure that it is a hexidecimal character.
*
* @throws com.mongodb.util.JSONParseException
* if the current character is not a hexidecimal character
*/
public void readHex() {
if (pos < s.length() &&
((s.charAt(pos) >= '0' && s.charAt(pos) <= '9') ||
(s.charAt(pos) >= 'A' && s.charAt(pos) <= 'F') ||
(s.charAt(pos) >= 'a' && s.charAt(pos) <= 'f'))) {
pos++;
} else {
throw new JSONParseException(s, pos);
}
}
/**
* Checks the current character, making sure that it is the expected character.
*
* @param ch the character expected
* @throws com.mongodb.util.JSONParseException
* if the current character does not match the given character
*/
public boolean check(char ch) {
return get() == ch;
}
/**
* Advances the position in the string past any whitespace.
*/
public void skipWS() {
while (pos < s.length() && Character.isWhitespace(s.charAt(pos))) {
pos++;
}
}
/**
* Returns the current character.
* Returns -1 if there are no more characters.
*
* @return the next character
*/
public char get() {
skipWS();
if (pos < s.length()) {
return s.charAt(pos);
}
return (char) -1;
}
/**
* Parses a string.
*
* @return the next string.
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
public String parseString(boolean needQuote) {
char quot = 0;
if (check('\'')) {
quot = '\'';
} else if (check('\"'))
quot = '\"';
else if (needQuote)
throw new JSONParseException(s, pos);
char current;
if (quot > 0) {
read(quot);
}
StringBuilder buf = new StringBuilder();
int start = pos;
while (pos < s.length()) {
current = s.charAt(pos);
if (quot > 0) {
if (current == quot) {
break;
}
} else {
if (current == ':' || current == ' ') {
break;
}
}
if (current == '\\') {
pos++;
char x = get();
char special = 0;
switch (x) {
case 'u': { // decode unicode
buf.append(s.substring(start, pos - 1));
pos++;
int tempPos = pos;
readHex();
readHex();
readHex();
readHex();
int codePoint = Integer.parseInt(s.substring(tempPos, tempPos + 4), 16);
buf.append((char) codePoint);
start = pos;
continue;
}
case 'n':
special = '\n';
break;
case 'r':
special = '\r';
break;
case 't':
special = '\t';
break;
case 'b':
special = '\b';
break;
case '"':
special = '\"';
break;
case '\\':
special = '\\';
break;
}
buf.append(s.substring(start, pos - 1));
if (special != 0) {
pos++;
buf.append(special);
}
start = pos;
continue;
}
pos++;
}
buf.append(s.substring(start, pos));
if (quot > 0) {
read(quot);
}
return buf.toString();
}
/**
* Parses a number.
*
* @return the next number (int or double).
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
public Number parseNumber() {
char current = get();
int start = this.pos;
boolean isDouble = false;
if (check('-') || check('+')) {
pos++;
}
outer:
while (pos < s.length()) {
switch (s.charAt(pos)) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
pos++;
break;
case '.':
isDouble = true;
parseFraction();
break;
case 'e':
case 'E':
isDouble = true;
parseExponent();
break;
default:
break outer;
}
}
if (isDouble) {
return Double.valueOf(s.substring(start, pos));
}
Long val = Long.valueOf(s.substring(start, pos));
if (val <= Integer.MAX_VALUE) {
return val.intValue();
}
return val;
}
/**
* Advances the pointed through <i>.digits</i>.
*/
public void parseFraction() {
// get past .
pos++;
outer:
while (pos < s.length()) {
switch (s.charAt(pos)) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
pos++;
break;
case 'e':
case 'E':
parseExponent();
break;
default:
break outer;
}
}
}
/**
* Parses javascript function.
*/
public String parseFunction() {
Stack stack = new Stack();
int start = pos;
read('{');
stack.push('{');
while (!stack.empty()) {
char current = read();
if (current == '{') {
stack.push(current);
}
if (current == '}') {
stack.pop();
}
}
return s.substring(start, pos);
}
/**
* Advances the pointer through the exponent.
*/
public void parseExponent() {
// get past E
pos++;
if (check('-') || check('+')) {
pos++;
}
outer:
while (pos < s.length()) {
switch (s.charAt(pos)) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
pos++;
break;
default:
break outer;
}
}
}
/**
* Parses the next array.
*
* @return the array
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
public Object parseArray() {
return parseArray(null);
}
/**
* Parses the next array.
*
* @return the array
* @throws com.mongodb.util.JSONParseException
* if invalid JSON is found
*/
protected Object parseArray(String name) {
if (name != null) {
_callback.arrayStart(name);
} else {
_callback.arrayStart();
}
read('[');
int i = 0;
char current = get();
while (current != ']') {
String elemName = String.valueOf(i++);
Object elem = parse(elemName);
doCallback(elemName, elem);
if ((current = get()) == ',') {
read(',');
} else if (current == ']') {
break;
} else {
throw new JSONParseException(s, pos);
}
}
read(']');
return _callback.arrayDone();
}
}