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Unreachable Statement with Break

So I had a previous question but realized I posted the wrong offending code. I've marked the offending statements below.

What I am trying to do is set the precedence for each of the operators with that switch statement.

Maybe someone could point me in the right direction.

Just as a note, I AM running JAVA 7 so String Switch will work.

Code

opType.java

import java.io.*;

public final class opType {

   public static opType ADD = new opType( "Add" );
   public static opType SUB = new opType( "Sub" );
   public static opType MULT = new opType( "Mult" );
   public static opType DIV = new opType( "Div" );
   public static opType MOD = new opType( "Mod" );
   public static opType LPAR = new opType( "LParen" );
   public static opType RPAR = new opType( "RParen" );

   protected String name;

   private opType( String n )
   {
      name = n;
   }

   public String getName()
   {
      return name;
   }

Operator.java

public class Operator extends Token {

    protected opType val;

    public boolean isOperator() { return true; }
    public boolean isOperand() { return false; }

    protected int getPrec()
    {

        switch(val.getName())
        {
            case "LParen": 
            {
                return 0;
                break; //unreachable
            }

            case "RParen": 
            {
                return 0;
                break; //unreachable
            }

            case "Mult":
            {
                return 1;
                break; //unreachable
            }
            case "Div": 
            {   
                return 1;
                break; //unreachable
            }
            case "Mod": 
            {   
                return 1;
                break; //unreachable
            }
            case "Add": 
            {   
                return 2;
                break; //unreachable
            }
            case "Sub": 
            {   
                return 2;
                break; //unreachable
            }
        }

            return 0;
    }

    public static int compare( Operator a, Operator b )
    {
        if( a.getPrec() == b.getPrec() )
            return 0;
        else if( a.getPrec() < b.getPrec() )
            return -1;
        else
            return 1;
    }

    public opType getVal() { return val; }

    public Operator( opType v ) { val = v; }

}
like image 902
KyleCrowley Avatar asked Nov 28 '22 04:11

KyleCrowley


1 Answers

If you put a return, then the function returns before the break is executed and therefore the break will never be reached.

Instead you could use a variable that you set to a desired value and after the switch return that. Or just get rid of the break statements.

like image 61
Blub Avatar answered Dec 13 '22 08:12

Blub