variableDeclarationValidate.java

package computergraphics;

import java.util.ArrayList;

public class Test {

	public static void main(String[] args) {
		validate("int dd,b, ZA,A, A, ddd,ac,a;");
	}

	public static void validate(String statements) {
		ArrayList<String> vn = new ArrayList<String>();
		
        String[] tokens = statements.trim().split(",");
        
        if(!tokens[0].contains(" ")) {
        	System.out.println("Missing space in datatype");
            return;
        }

        String[] dv = tokens[0].split(" ");
        tokens[0] = dv[1].trim();
        
        String[] last = tokens[tokens.length - 1].trim().split(";");        

        if(last.length > 1 || last.length < 1) {
        	System.out.println("Invalid semicolon");
            return;
        }            

        tokens[tokens.length-1] = last[0];

        for(String token : tokens) {
            for(char l : token.trim().toCharArray()) {
                if((l < 65 && l > 90) || (l < 97 && l > 122)) {
                	System.out.println("Invalid variable name");
                    return;
                }                
            }    
            
            if(vn.contains(token.trim())) {
            	System.out.println("Duplicate variable name");
            	return;
            }
            
            vn.add(token.trim());
        }

        System.out.println("Valid declarations!");
    }
}