com.api.jsonata4java.expressions.functions.FormatBaseFunction Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of JSONata4Java Show documentation
Port of jsonata.js to Java to enable rules for JSON content
There is a newer version: 2.5.1
/**
 * (c) Copyright 2018, 2019 IBM Corporation
 * 1 New Orchard Road, 
 * Armonk, New York, 10504-1722
 * United States
 * +1 914 499 1900
 * support: Nathaniel Mills [email protected]
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.api.jsonata4java.expressions.functions;

import com.api.jsonata4java.expressions.EvaluateRuntimeException;
import com.api.jsonata4java.expressions.ExpressionsVisitor;
import com.api.jsonata4java.expressions.generated.MappingExpressionParser.Function_callContext;
import com.api.jsonata4java.expressions.utils.Constants;
import com.api.jsonata4java.expressions.utils.FunctionUtils;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.fasterxml.jackson.databind.node.TextNode;

/**
 * From http://docs.jsonata.org/string-functions.html:
 * 
 * $formatBase(number [, radix])
 * 
 * Casts the number to a string and formats it to an integer represented in the
 * number base specified by the radix argument. If radix is not specified, then
 * it defaults to base 10. radix can be between 2 and 36, otherwise an error is
 * thrown.
 * 
 * $formatBase(100, 2)==“1100100” $formatBase(2555, 16)=="9fb"
 * 
 */
public class FormatBaseFunction extends FunctionBase implements Function {

	public static String ERR_BAD_CONTEXT = String.format(Constants.ERR_MSG_BAD_CONTEXT, Constants.FUNCTION_FORMAT_BASE);
	public static String ERR_ARG1BADTYPE = String.format(Constants.ERR_MSG_ARG1_BAD_TYPE,
			Constants.FUNCTION_FORMAT_BASE);
	public static String ERR_ARG2BADTYPE = String.format(Constants.ERR_MSG_ARG2_BAD_TYPE,
			Constants.FUNCTION_FORMAT_BASE);
	public static String ERR_ARG3BADTYPE = String.format(Constants.ERR_MSG_ARG3_BAD_TYPE,
			Constants.FUNCTION_FORMAT_BASE);

	public JsonNode invoke(ExpressionsVisitor expressionVisitor, Function_callContext ctx) {
		// Create the variable to return
		JsonNode result = null;

		// Retrieve the number of arguments
		JsonNode argNumber = JsonNodeFactory.instance.nullNode();
		boolean useContext = FunctionUtils.useContextVariable(this, ctx, getSignature());
		int argCount = getArgumentCount(ctx);
		if (useContext) {
			argNumber = FunctionUtils.getContextVariable(expressionVisitor);
			if (argNumber != null && argNumber.isNull() == false) {
				argCount++;
			} else {
				useContext = false;
			}
		}

		// Make sure that we have the right number of arguments
		if (argCount == 1 || argCount == 2) {
			if (!useContext) {
				argNumber = FunctionUtils.getValuesListExpression(expressionVisitor, ctx, 0);
			}

			// Make sure that the first argument is a number
			if (argNumber == null) {
				return null;
			}
			if (argNumber.isNumber()) {
				// Read the number from the argument
				Double d = argNumber.asDouble();
				Long l = Math.round(d);
				if (Math.abs((double)l -d) == 0.5 && l % 2 == 1) {
					l--;
				}
				final int number = (int)l.longValue();

				// Check to see if we have an radix argument and read it if we do
				int radix = 10;
				if (argCount == 2) {
					final JsonNode argRadix = FunctionUtils.getValuesListExpression(expressionVisitor, ctx,
							useContext ? 0 : 1);
					if (argRadix != null) {
						if (argRadix.isNumber()) {
							d = argRadix.asDouble();
							l = Math.round(d);
							if (Math.abs((double)l - d) == 0.5 && l % 2 == 1) {
								l--;
							}
							radix = (int)l.longValue();

							// Make sure that the radix specified is valid
							if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX) {
								throw new EvaluateRuntimeException(Constants.ERR_MSG_INVALID_RADIX);
							}
						} else {
							throw new EvaluateRuntimeException(ERR_ARG2BADTYPE);
						}
					}
				}

				// Convert the number to a string in the specified base
				result = new TextNode(Integer.toString(number, radix));
			} else {
				throw new EvaluateRuntimeException(ERR_ARG1BADTYPE);
			}
		} else {
			throw new EvaluateRuntimeException(argCount == 0 ? ERR_BAD_CONTEXT : ERR_ARG3BADTYPE);
		}

		return result;
	}

	@Override
	public int getMaxArgs() {
		return 2;
	}
	@Override
	public int getMinArgs() {
		return 0; // account for context variable
	}

	@Override
	public String getSignature() {
		// accepts a number (or context variable), an optional number, returns a string
		return "";
	}
}