Exercise 1

What is the relationship between the two local variables called temp?
What is the scope of each of these two variables?
Suppose now that we introduce a field called temp.
1. What is the scope of each of the local variables now ?
2. What is the scope of the field called temp ?
3. How would we access this field's value from within report()?

public class ArrayHwk1
{
	// constructor here
	
	public void report()
	{
		double temp = rainiest();
		System.out.println(′′Most rain: ′′ + temp + ′′mm′′);
		// other code here
	}
	
	private double rainiest()
	{
		double temp;
		// code to find most rainfall here and to store
		// it in the local variable temp
		return temp;
	}
	
	// other code here
}

There is no relationship between 2 local variables.
The lifetime of both local variables, temp, is the method in which they are created.
.
1. The scope is unchanged, since the local variables are still created in the method.
2. The field variable's scope is the entire class, aside from where the local variables are created.
3. By using this.temp, we can access the class's field variable

Exercise 2

class Param1
{
	public final float fixed = 50;
	public double a;
	private int b;
	public float c;
	
	// constructor here
	
	public float method1(int z)
	{
		return (float) z; //H
	}
	
	private void method2(double y)
	{
		c = y; //I double to float error
	}
	
	public int method3()
	{
		return b; //J
	}
}

tester.fixed = 25; // Statement A fixes is final, immutable. tester.b = 50; // Statement B b is private, cannot directly modify. tester.c = 5.0; // Statement C c is a float, cannot assign double. int y = tester.method1(); // Statement D logic error: not given parameter, cannot assign float to int. tester.method2(10.0f); // Statement E method2 is private. float y = tester.method3(); // Statement F no error, implicit typecast int to float. double y = tester.method1(30); // Statement G no error, implicit typecast int to float to double.

Exercise 3

class Param1
{
	private int score;
	
	// default constructor here
	
	public void method1(int y)
	{
		score = y;
	}
	
	public int getScore()
	{
		return score;
	}
}

Param1 q1 = new Param1(); q1.method1(100); System.out.println(q1.getScore());```

score = 100

class Param2
{
	public int x;
	// default constructor here
	public void method1(int y)
	{
		x = 4*y;
	}
	
	public int getX()
	{
		return x;
	}
}

Param2 q2 = new Param2(); int y = 25; // Local Variable. q2.method1(y); System.out.println(y); System.out.println(q2.getX());

y = 25
x = 100

class Param3
{
	public int x;
	// default constructor here
	private void increase(int p)
	{
		x = x*p;
	}
	
	public void calculateX(int y)
	{
		increase(y);
	}
	
	public int getX()
	{
		return x;
	}
}

Param3 q3 = new Param3(); q3.x = 5; q3.calculateX(7); increase(7) -> x(5) = x(5) * 7 -> 5 * 7 = 35 System.out.println(q3.getX());

x = 35

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Exercise 1

Exercise 2

Exercise 3

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