aquaduck97 Posts - Answer Overflow

aquaduck97

•Created by aquaduck97 on 9/27/2024 in #java-help

Weird issue that gets solved by wrapping it in a try/catch but it never gets caught

I'm coming from C# and learning Java and I stumbled across a bit of a weird issue with String.startsWith and String.equals in foreach loops. I have a method to which I pass a String array, in this method I have a foreach loop that checks each string to a specific value using String.startsWith. If I DON'T wrap the loop in a try/catch I get an error that says the current array item is null when it doesn't match, but if I DO wrap it and put a breakpoint or println in the catch block, it's perfectly fine and I don't get any errors and the exception is never caught. The method (simplified):

public void compareString(String[] arr) {
    String val = "";
    boolean isValid = false;
    do {
      val = new Scanner(System.in).nextLine();
      for(String word : arr) {
        // Can print every word just fine
        //Try/catch required here or errors at next line if sourcing "arr"
        if(word.startsWith(val){ // Errors with null exception for "word" even though word is not null
          isValid = true;
        }
        //Try/catch end
      }
      if(!isValid)
        //  Prints error
    } while(!isValid);

public void compareString(String[] arr) {
    String val = "";
    boolean isValid = false;
    do {
      val = new Scanner(System.in).nextLine();
      for(String word : arr) {
        // Can print every word just fine
        //Try/catch required here or errors at next line if sourcing "arr"
        if(word.startsWith(val){ // Errors with null exception for "word" even though word is not null
          isValid = true;
        }
        //Try/catch end
      }
      if(!isValid)
        //  Prints error
    } while(!isValid);

If I hardcoded an array in the method it worked perfectly fine without a try/catch

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