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import org.graalvm.compiler.hotspot.stubs.DivisionByZeroExceptionStub;
>>>>>>> 2ffc5ca1cddf44a1e6d380f18eb4b10bb4578efb
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
/**
* Calculator resource exposed at '/calculator' path
*/
@Path("/calculator")
public class CalculatorResource {
/**
* Method handling HTTP POST requests. The calculated answer to the expression will be sent to the client as
* plain/text.
*
* @param expression the expression to be solved as plain/text.
* @return solution to the expression as plain/text or -1 on error
*/
@POST
@Consumes(MediaType.TEXT_PLAIN)
@Produces(MediaType.TEXT_PLAIN)
public int calculate(String expression) {
// Removes all whitespaces
String expressionTrimmed = expression.replaceAll("\\s+", "");
int result = -1;
/*
* .matches use regex expression to decide if a String matches a given pattern.
* [0-9]+[+][0-9]+ explained:
* [0-9]+: a number from 0-9 one or more times. For example 1, 12 and 123.
* [+]: the operator + one time.
* The total regex expression accepts for example:
* 12+34,
* 1+2,
* 10000+1000
if (expressionTrimmed.matches("^\\d+(?:\\s*[+]\\s*\\d+)*$")) result = sum(expressionTrimmed);
else if (expressionTrimmed.matches("^\\d+(?:\\s*[-]\\s*\\d+)*$")) result = subtraction(expressionTrimmed);
else if (expressionTrimmed.matches("^\\d+(?:\\s*[*]\\s*\\d+)*$")) result = multiplication(expressionTrimmed);
else if (expressionTrimmed.matches("^\\d+(?:\\s*[/]\\s*\\d+)*$")) result = division(expressionTrimmed);
return result;
}
public int multiplication(String equation) {
int sum = Integer.parseInt(split[0]);
try{
for (int i = 1; i < split.length; i++) {
if(!(split[i]).equals("0")) {
sum *= Integer.parseInt(split[i]);
}else throw new IllegalArgumentException(" Number can't be zero");
return sum;
}catch(IllegalArgumentException e){
e.printStackTrace();
}return -1;
public int division(String equation){
int sum = Integer.parseInt(split[0]);
for (int i = 1; i < split.length; i++) {
if(!(split[i]).equals("0")){
sum = Integer.parseInt(split[i]);
}else throw new IllegalArgumentException("Number can't be zero");
}catch (IllegalArgumentException e){
e.printStackTrace();
}return -1;
/**
* Method used to calculate a sum expression.
* @param expression the equation to be calculated as a String
* @return the answer as an int
*/
public int sum (String expression){
int sum = Integer.parseInt(split[0]);
for (int i = 1; i < split.length; i++) {
sum += Integer.parseInt(split[i]);
}
/**
* Method used to calculate a subtraction expression.
* @param expression the expression to be calculated as a String
* @return the answer as an int
*/
public int subtraction (String expression){
int sum = Integer.parseInt(split[0]);
for (int i = 1; i < split.length; i++) {
sum -= Integer.parseInt(split[i]);
}