Homework 3-3-2008

1. Explain bytecode, JVM
bytecode:是一種中間語言，可以稱為Java byte-code 或是簡稱為 byte-code，當初之所以要發展的原因是為了讓這語言能在不同的機械中運作，而它具有許多的特性:很小, 很容易上手, 而且並不貴等因素，而他負責編譯機械語言，讓使用者變於撰寫

JVM:JVM是一個虛構出來的電腦，並且屏蔽了原有的處理系統的指令，讓JAVA可以有自己的CPU等相關指令，使JAVA可以在任何平台都可以修改
2. Explain class, object

class: A Java program is divided into smaller parts called classes, and normally each class definition is in a separate file and is compiled separately.

object: To make sure it is clear which program we mean, we call the input program, which in our case will be a Java program, the source program, or source code, and call the translated low-level-language program that the compiler produces the object program, or object code.

3. Reading Assignments
Read 1.1, 1.2, 1.3 of Textbook

4.1 Write a Java program as follows:

Let i=2;

Print i;

Print 2 * (i++);

Print i;

public class I


{

public static void main(String[] args)



{
int i;/*虛告一個i的函數*/
i = 2;
System.out.println(i);/*輸出i值*/
System.out.println(2*(i++));/*輸出2乘與i++後的值*/
System.out.println(i);

}


}

4.2 Write a Java program as follows:

Let i=2;

Print i;

Print 2 * (++i);

Print i;

package homework;

public class I

{

public static void main(String[] args)

{

int i;/*虛告一個i的函數*/

i = 2;

System.out.println(i);/*輸出i值*/

System.out.println(2*(++i));/*輸出2乘與++i後的值*/

System.out.println(i);

}

}

4.3 Write a Java program as follows:

Let m=7, n=2;

Print (double) m/n;

Print m/ (double)n;

public class I

{

public static void main(String[] args)

{

int m,n;/*虛告m和n的函數*/

m = 7; n = 2;

System.out.println((double)m/n);

System.out.println(m/(double)n);

}

}