Thread: Delimiter function and number of words in string

Up, working on my java skills.
The isDelimiter function is suppose to return true if there is a delimiter in the string and false otherwise. The main is suppose to call this function and count the number of words in the string:

Here is what I came up with:

import java.util.*;
 
public class NumberOfWordsInString {
	public static void main (String[] args){
		Scanner in= new Scanner (System.in);
		String s;
		int count =0;
		char ch [] = new char [s.length];
		System.out.printf("Enter string\n");
		s= in.nextLine();
 
		for (int i = 0; i <s.length(); i++)
		{
			ch[i] = s.charAt(i);
			if (isDelimiter (ch))
			{
				count ++;
 
			}
		}
		System.out.printf("%d\n", count);
 
	}
 
 
 
public static boolean isDelimiter (char c){
 
	if (ch!= delimiter)
	{
		return false;
	}
 
	else return true;	
	}
}

Somehow my method isn't being successfully called by my main and the following error msg was received:
Exception in thread "main" java.lang.Error: Unresolved compilation problems:
length cannot be resolved or is not a field
The method isDelimiter(char) in the type NumberOfWordsInString is not applicable for the arguments (char[])

at javaimprovements.NumberOfWordsInString.main(Number OfWordsInString.java:10)


line 10:
char ch [] = new char [s.length];

and the main doesn't call the isDelimiter function

and the main doesn't call the isDelimiter function

You don't know what the main() method is or isn't doing, because you have compiler errors that prevent the code from executing. Compiler errors occur before execution and prevent execution. Runtime errors occur during execution.

Fix your compiler errors and post the updated code with any remaining questions.

Adding to GregBrannon's post, just so that it is completely clear to you, whenever you see "Unresolved compilation problems", 1 of 2 things will happen if you try to execute the program:

1. the program will not run at all if previously there hasn't been a successful compilation (i.e., a corresponding .class file hasn't been generated)
2. the program will run but will run against a .class file generated from a previous successful compilation (and so code added since the last successful compilation will not be executed)

length cannot be resolved or is not a field

The problem is at

String s;
int count = 0;
char ch[] = new char[s.length];

There are 2 problems here:

1. length refers to a field, and the String class does not have such a field. (See String (Java Platform SE 7 ).) To call a method it should be length().
2. The String s has been declared but not assigned anything.

The method isDelimiter(char) in the type NumberOfWordsInString is not applicable for the arguments (char[])

In the main method you have

char ch[] = new char[s.length];
...
 
for (int i = 0; i < s.length(); i++) {
    ch[i] = s.charAt(i);
    if (isDelimiter(ch)) {
        ...

ch is declared as a char array, but the isDelimiter() method signature is

public static boolean isDelimiter(char c)

where its parameter c is a char (not an array).

Note that there are further errors in the isDelimiter() method that prevent compilation, so you'll also have to fix those before you can execute this program.

Thanks for the guidance.
Here is the modified code:

import java.util.*;
 
public class NumberOfWordsInString {
	public static void main (String[] args){
		Scanner in= new Scanner (System.in);
		String s;
		int count =0;
		char ch;
		System.out.printf("Enter string\n");
		s= in.nextLine();
 
		for (int i = 0; i <s.length(); i++)
		{
			ch = s.charAt(i);
			if (isDelimiter (ch))
			{
				count ++;
 
			}
		}
		System.out.printf("%d\n", count);
 
	}
 
 
public static boolean isDelimiter (char ch){
Scanner in = new Scanner (System.in);
 
while (ch != '\n')
	if (ch!= '.' ||ch != '!'|| ch != '?')
	{
		return false;
	}
 
	else return true;	
	}
    ch= in.nextLine();
}

However, how do read a single character from the keyboard?
My problem is the line:
ch= in.nextLine();