PHP Serialized array/string/integer parser in Groovy

PhpSerializedParser.groovy

package ch.prodema.misc
class PhpSerializedParser {

	private enum ObjectType {
		ARRAY('a'), STRING('s'), INTEGER('i')

		ObjectType(String typeChar) { this.typeChar = typeChar }
		private final String typeChar
		private static final Map<String,ObjectType> lookup
		static {
			lookup = new HashMap<String,ObjectType>()
			for(ObjectType objType in EnumSet.allOf(ObjectType.class)) {
				lookup.put(objType.value(), objType)
			}
		}
		public String value() { return typeChar }
		public static ObjectType typeForChar(String typeChar) {
			return lookup.get(typeChar)
		}
	}

	private String input
	private int cursor = 0

	PhpSerializedParser(String input) {
		this.input = input
	}

	def parse() {
		def type = ObjectType.typeForChar input[cursor]
		cursor += 2 // skip the typeof and the subsequent colon
		def result
		switch(type) {
			case ObjectType.STRING:
				readToken() // to skip the string length
				result = readString()
			break
			case ObjectType.INTEGER:
				result = readInt()
			break
			case ObjectType.ARRAY:
				result = readArray()
			break
		}
		return result
	}

	private String readToken() {
		int tokenEndIndex1 = input.indexOf ";", cursor
		int tokenEndIndex2 = input.indexOf ":", cursor
		int tokenEndIndex
		if (tokenEndIndex2 < tokenEndIndex1 && tokenEndIndex2 != -1) {
			tokenEndIndex = tokenEndIndex2
		} else {
			tokenEndIndex = tokenEndIndex1
		}
		String result = input.substring cursor, tokenEndIndex
		cursor = tokenEndIndex + 1
		return result
	}

	private String readChar() {
		String c = this.input[cusor]
		cursor++
		return c
	}

	private void skipChar() { cursor++ }

	private int readInt() {
		String token = readToken()
		return Integer.valueOf(token)
	}

	private String tokenToString(String token) {
		return token.substring(1, token.size() - 1)
	}

	private String readString() {
		String token = readToken()
		return tokenToString(token)
	}

	private def readArray() {
		int numElements = readInt()
		skipChar() // open brace for array

		List keys = []
		List values = []

		for(int i = 0; i < numElements; i++) {
			keys.push parse()
			values.push parse()
		}

		skipChar() // close brace for array
		skipChar() // semicolon to end token

		// check if array was a list or should be a map
		def listKeys = 0..<numElements
		boolean isList = true
		for(int i = 0; i < numElements; i++) {
			if(keys[i] != listKeys[i]) {
				isList = false
				break;
			}
		}

		def result
		if(isList) {
			result = values
		} else {
			result = [:]
			for(int i = 0; i < numElements; i++) {
				result.put keys[i], values[i]
			}
		}

		return result
	}

}

UsageExample.groovy

import ch.prodema.misc.PhpSerializedParser

def input = /a:3:{s:4:"test";a:1:{i:3;i:5;};s:5:"field";s:19:"Geometric_intensity";s:6:"values";a:5:{i:0;s:0:"";i:1;s:4:"Good";i:2;s:4:"Fair";i:3;s:4:"Poor";i:4;s:12:"Unacceptable";}}/

def p = new PhpSerializedParser(input)
def x = p.parse()

// Result: x ==> {test={3=5}, field=Geometric_intensity, values=[, Good, Fair, Poor, Unacceptable]}