public class ControlStructures {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		
		
		/*
		 * How can we build boolean expressions ?
		 * a. Use boolean literals
		 * b. Use relational operators and 
		 * c. Use method calls 
		 *  
		 */
		
				
		boolean programStarted=true;
		if(programStarted)							
			System.out.println("Program has started");
		
						
		
		
		int a=5;
		int b=10;
		int dummy=0;
		if(a>b){
			System.out.println("a="+a+" is larger than b="+b);			
		}
		
		System.out.println("You need to use braces if you have multiple conditional statements");
		if(a>b)
			dummy=dummy+1;
			System.out.println("a="+a+" is larger than b="+b);			
		
	    if(a>b){
	    	dummy=dummy+1;
			System.out.println("a="+a+" is larger than b="+b);
		}
		
	    // braces serve to group statements. The build the body of the conditional statement.
	    
	    
	    
		String sentence="John goes to the school.";
		if(sentence.startsWith("John")){
			System.out.println("We are talking about John.");			
		}
		else{
			System.out.println("We are talking about someone else.");
		}
		
		
	    /* 
	     * if ... else if... else
	     *
	     * 
	     */
		
		int c=40;
		
		if(c<20){
			System.out.println("c is less than 20");
		}
		else if(c<50){
			System.out.println("c is (larger or equal) than 20 and is less than 50");
		}
		else if(c<60){
			System.out.println("c is (larger or equal) than 50 and is less than 60");
		}
		else{
			System.out.println("c is larger than 60");
		}
		
		
		
		if(c<20){
			System.out.println("c is less than 20");
		}
		if(c<50){
			System.out.println("c is less than 50");
		}
		if(c<60){
			System.out.println("c is less than 60");
		}
		
		
				
		/*
		 * 
		 * Nested if statements
		 * Each entered if-branch provides us with additional information
		 * Nested if statements provides step-by-step refinement of the condition. Thus they make code more readable.
		 */
		
		int d=40;
		if(d<50){
			if(d>=30){
				System.out.println("d is less than 50 and (equal or greater) than 30");
			}
			else{
				System.out.println("d is less than 50 and is less than 30. This means it is less than 30");
			}			
		}
		
		if(d<50 && d>=30){
			System.out.println("d is less than 50 and (equal or greater) than 30");
		}
		else{
			System.out.println("d is less than 50 and is less than 30. This means it is less than 30");
		}
		

		/*
		 * 
		 * To compare Strings use equals
		 *
		 */
		
		String x="Car";
	     
//	    if(x==args[0]){
//	    	 System.out.println("The value of the string variable is \"Car\"");	    	 
//	    }
//	    else{
//	    	 System.out.println("The value of the string variable is not \"Car\"");
//	    }
//	     
//	    if(x.equals(args[0])){
//	    	 System.out.println("The value of the string variable is \"Car\"");	    	 
//	    }
//	    else{
//	    	 System.out.println("The value of the string variable is not \"Car\"");
//	    }
	     
	     
	
	
	}
	
	
	

}