Java. Massimo Dong. November 27, Massimo Dong Java November 27, / 26

Size: px
Start display at page:

Download "Java. Massimo Dong. November 27, Massimo Dong Java November 27, / 26"

Transcription

1 Java Massimo Dong November 27, 2017 Massimo Dong Java November 27, / 26

2 Outline 1 The Java Language Java Virtual Machine(JVM) 2 Java Memory Management References & Garbage Collection Array Check *Heartbleed 3 Compile & Run Time Check Exceptions Type Safety Modifiers Undefined Behaviors 4 Java Rich Internet Applications Web Start Applications Sandbox Security Manager Signing Massimo Dong Java November 27, / 26

3 Java Virtual Machine(JVM) Massimo Dong Java November 27, / 26

4 Outline 1 The Java Language Java Virtual Machine(JVM) 2 Java Memory Management References & Garbage Collection Array Check *Heartbleed 3 Compile & Run Time Check Exceptions Type Safety Modifiers Undefined Behaviors 4 Java Rich Internet Applications Web Start Applications Sandbox Security Manager Signing Massimo Dong Java November 27, / 26

5 References vs Pointers Java ProblemSolving ref = new ProblemSolving();... C++ ProblemSolving *ptr = new ProblemSolving;... delete ptr; Massimo Dong Java November 27, / 26

6 Java Reference Java static void foo(problemsolving ref){ ref.ud = 2; public static void main(string[] argv){ ProblemSolving ref = new ProblemSolving(); foo(ref); System.out.println(ref.UD); Massimo Dong Java November 27, / 26

7 Java Reference Java static void foo(problemsolving ref){ ref.ud = 2; public static void main(string[] argv){ ProblemSolving ref = new ProblemSolving(); foo(ref); System.out.println(ref.UD); 2 Massimo Dong Java November 27, / 26

8 Java Arrays An object is a class instance or an array. Massimo Dong Java November 27, / 26

9 Java Arrays An object is a class instance or an array. Java public class ArrayDemo{ public static void main(string[] argv){ int[] A = new int[10]; System.out.println(A instanceof Object); Massimo Dong Java November 27, / 26

10 Java Arrays An object is a class instance or an array. Java public class ArrayDemo{ public static void main(string[] argv){ int[] A = new int[10]; System.out.println(A instanceof Object); true Massimo Dong Java November 27, / 26

11 Array Check Java public class ArrayDemo{ public static void main(string[] argv){ int[] A = new int[10]; System.out.println(A[233]); Massimo Dong Java November 27, / 26

12 Array Check Java public class ArrayDemo{ public static void main(string[] argv){ int[] A = new int[10]; System.out.println(A[233]); Exception in thread "main" java.lang.arrayindexoutofboundsexception: 233 at ArrayDemo.main(ArrayDemo.java:4) Massimo Dong Java November 27, / 26

13 Heartbleed Massimo Dong Java November 27, / 26

14 Heartbleed Massimo Dong Java November 27, / 26

15 Heartbleed Massimo Dong Java November 27, / 26

16 Heartbleed C/C++ memcpy(bp, pl, payload); Massimo Dong Java November 27, / 26

17 Heartbleed C/C++ memcpy(bp, pl, payload); pl = "ProblemSolving" payload = 64 * 1024; Massimo Dong Java November 27, / 26

18 Massimo Dong Java November 27, / 26

19 Massimo Dong Java November 27, / 26

20 Outline 1 The Java Language Java Virtual Machine(JVM) 2 Java Memory Management References & Garbage Collection Array Check *Heartbleed 3 Compile & Run Time Check Exceptions Type Safety Modifiers Undefined Behaviors 4 Java Rich Internet Applications Web Start Applications Sandbox Security Manager Signing Massimo Dong Java November 27, / 26

21 Exceptions Java public static void main(string[] argv){ FileInputStream in = new FileInputStream("data.in"); Massimo Dong Java November 27, / 26

22 Exceptions Java public static void main(string[] argv){ FileInputStream in = new FileInputStream("data.in"); error: unreported exception FileNotFoundException; must be caught or declared to be thrown FileInputStream in = new FileInputStream("data.in"); ^ Massimo Dong Java November 27, / 26

23 Exceptions Java try{ FileInputStream in = new FileInputStream("data.in"); catch(filenotfoundexception E){ System.out.println("File Not Found!"); Massimo Dong Java November 27, / 26

24 Exceptions Java try{ FileInputStream in = new FileInputStream("data.in"); catch(filenotfoundexception E){ System.out.println("File Not Found!"); Java public static void main(string[] argv) throws FileNotFoundException{ FileInputStream in = new FileInputStream("data.in"); Massimo Dong Java November 27, / 26

25 Type Safety C int main(){ void (*foo)(); foo = 233; foo(); Massimo Dong Java November 27, / 26

26 Type Safety C int main(){ void (*foo)(); foo = 233; foo(); warning: assignment makes pointer from integer without a cast foo = 233; ^ Massimo Dong Java November 27, / 26

27 Type Safety Java public static void main(string[] argv){ A a; B b; a = b; C int main(){ struct A *a; struct B *b; a = b; Massimo Dong Java November 27, / 26

28 Modifiers Access Modifiers private public protected Non Access Modifiers static final abstract synchronized and volatile Massimo Dong Java November 27, / 26

29 Java public static void main(string[] argv){ final int a; a = 39; Massimo Dong Java November 27, / 26

30 Java public static void main(string[] argv){ final int a; a = 39; public static void main(string[] argv){ final int a; a = 39; a = 40; Massimo Dong Java November 27, / 26

31 Java public static void main(string[] argv){ final int a; a = 39; public static void main(string[] argv){ final int a; a = 39; a = 40; error: variable a might already have been assigned Massimo Dong Java November 27, / 26

32 Undefined Behaviors Massimo Dong Java November 27, / 26

33 Undefined Behaviors C i = i++ + 1; Massimo Dong Java November 27, / 26

34 Undefined Behaviors C i = i++ + 1; Undefined Behavior Massimo Dong Java November 27, / 26

35 Undefined Behaviors C i = i++ + 1; Undefined Behavior Java i = i++ + 1; Massimo Dong Java November 27, / 26

36 Undefined Behaviors C i = i++ + 1; Undefined Behavior Java i = i++ + 1; 1 Massimo Dong Java November 27, / 26

37 Outline 1 The Java Language Java Virtual Machine(JVM) 2 Java Memory Management References & Garbage Collection Array Check *Heartbleed 3 Compile & Run Time Check Exceptions Type Safety Modifiers Undefined Behaviors 4 Java Rich Internet Applications Web Start Applications Sandbox Security Manager Signing Massimo Dong Java November 27, / 26

38 Web Start Applications Demo Massimo Dong Java November 27, / 26

39 Sandbox Massimo Dong Java November 27, / 26

40 Sandbox Java try{ FileInputStream in = new FileInputStream("input.txt"); catch(exception E){ System.out.println(E); Massimo Dong Java November 27, / 26

41 Sandbox Java try{ FileInputStream in = new FileInputStream("input.txt"); catch(exception E){ System.out.println(E); java.security.accesscontrolexception: access denied ("java.io.filepermission" "input.txt" "read") Massimo Dong Java November 27, / 26

42 Security Manager Java SecurityManager security = System.getSecurityManager(); if(security!= null){ try{ security.checkread("input.txt"); catch(exception E){ System.out.println(E); return; Massimo Dong Java November 27, / 26

43 Security Manager Java SecurityManager security = System.getSecurityManager(); if(security!= null){ try{ security.checkread("input.txt"); catch(exception E){ System.out.println(E); return; $javaws -nosecurity demo_no_codebase.jnlp Massimo Dong Java November 27, / 26

44 Signing Massimo Dong Java November 27, / 26

45 Signing Demo Massimo Dong Java November 27, / 26

46 References Massimo Dong Java November 27, / 26

10/22/2018 Programming Data Structures

10/22/2018 Programming Data Structures 10/22/2018 Programming Data Structures Quiz 2 on Wednesday, Oct. 24! Assignment14 Quiz Content Recursion 1 Assignment14 public static int readlines(string filename) throws FileNotFoundException { FileInputStream

More information

CS/B.TECH/CSE(New)/SEM-5/CS-504D/ OBJECT ORIENTED PROGRAMMING. Time Allotted : 3 Hours Full Marks : 70 GROUP A. (Multiple Choice Type Question)

CS/B.TECH/CSE(New)/SEM-5/CS-504D/ OBJECT ORIENTED PROGRAMMING. Time Allotted : 3 Hours Full Marks : 70 GROUP A. (Multiple Choice Type Question) CS/B.TECH/CSE(New)/SEM-5/CS-504D/2013-14 2013 OBJECT ORIENTED PROGRAMMING Time Allotted : 3 Hours Full Marks : 70 The figures in the margin indicate full marks. Candidates are required to give their answers

More information

Object Oriented Programming Exception Handling

Object Oriented Programming Exception Handling Object Oriented Programming Exception Handling Budditha Hettige Department of Computer Science Programming Errors Types Syntax Errors Logical Errors Runtime Errors Syntax Errors Error in the syntax of

More information

Full file at Chapter 2 - Inheritance and Exception Handling

Full file at   Chapter 2 - Inheritance and Exception Handling Chapter 2 - Inheritance and Exception Handling TRUE/FALSE 1. The superclass inherits all its properties from the subclass. ANS: F PTS: 1 REF: 76 2. Private members of a superclass can be accessed by a

More information

The design of an ADT should evolve naturally during the problem-solving process Questions to ask when designing an ADT

The design of an ADT should evolve naturally during the problem-solving process Questions to ask when designing an ADT Designing an ADT The design of an ADT should evolve naturally during the problem-solving process Questions to ask when designing an ADT What data does a problem require? What operations does a problem

More information

1d: tests knowing about bitwise fields and union/struct differences.

1d: tests knowing about bitwise fields and union/struct differences. Question 1 1a: char ptr[] = Hello World ; char a = ptr[1], b = *(ptr+6); Creates an array of 12 elements, 11 visible letters and a character value 0 at the end. i true ii true iii false iv false v true

More information

Introduction. Exceptions: An OO Way for Handling Errors. Common Runtime Errors. Error Handling. Without Error Handling Example 1

Introduction. Exceptions: An OO Way for Handling Errors. Common Runtime Errors. Error Handling. Without Error Handling Example 1 Exceptions: An OO Way for Handling Errors Introduction Rarely does a program runs successfully at its very first attempt. It is common to make mistakes while developing as well as typing a program. Such

More information

Program Fundamentals

Program Fundamentals Program Fundamentals /* HelloWorld.java * The classic Hello, world! program */ class HelloWorld { public static void main (String[ ] args) { System.out.println( Hello, world! ); } } /* HelloWorld.java

More information

Administrivia. Java Review. Objects and Variables. Demo. Example. Example: Assignments

Administrivia. Java Review. Objects and Variables. Demo. Example. Example: Assignments CMSC433, Spring 2004 Programming Language Technology and Paradigms Java Review Jeff Foster Feburary 3, 2004 Administrivia Reading: Liskov, ch 4, optional Eckel, ch 8, 9 Project 1 posted Part 2 was revised

More information

ECE 462 Fall 2011, Third Exam

ECE 462 Fall 2011, Third Exam ECE 462 Fall 2011, Third Exam DO NOT START WORKING ON THIS UNTIL TOLD TO DO SO. You have until 9:20 to take this exam. Your exam should have 12 pages total (including this cover sheet). Please let Prof.

More information

Crash Course in Java. Why Java? Java notes for C++ programmers. Network Programming in Java is very different than in C/C++

Crash Course in Java. Why Java? Java notes for C++ programmers. Network Programming in Java is very different than in C/C++ Crash Course in Java Netprog: Java Intro 1 Why Java? Network Programming in Java is very different than in C/C++ much more language support error handling no pointers! (garbage collection) Threads are

More information

CSC System Development with Java. Exception Handling. Department of Statistics and Computer Science. Budditha Hettige

CSC System Development with Java. Exception Handling. Department of Statistics and Computer Science. Budditha Hettige CSC 308 2.0 System Development with Java Exception Handling Department of Statistics and Computer Science 1 2 Errors Errors can be categorized as several ways; Syntax Errors Logical Errors Runtime Errors

More information

CSPP : Introduction to Object-Oriented Programming

CSPP : Introduction to Object-Oriented Programming CSPP 511-01: Introduction to Object-Oriented Programming Harri Hakula Ryerson 256, tel. 773-702-8584 hhakula@cs.uchicago.edu August 7, 2000 CSPP 511-01: Lecture 15, August 7, 2000 1 Exceptions Files: Text

More information

CSC 1214: Object-Oriented Programming

CSC 1214: Object-Oriented Programming CSC 1214: Object-Oriented Programming J. Kizito Makerere University e-mail: jkizito@cis.mak.ac.ug www: http://serval.ug/~jona materials: http://serval.ug/~jona/materials/csc1214 e-learning environment:

More information

COE318 Lecture Notes Week 10 (Nov 7, 2011)

COE318 Lecture Notes Week 10 (Nov 7, 2011) COE318 Software Systems Lecture Notes: Week 10 1 of 5 COE318 Lecture Notes Week 10 (Nov 7, 2011) Topics More about exceptions References Head First Java: Chapter 11 (Risky Behavior) The Java Tutorial:

More information

Review what constitutes a thread Creating threads general Creating threads Java What happens if synchronization is not used? Assignment.

Review what constitutes a thread Creating threads general Creating threads Java What happens if synchronization is not used? Assignment. Review what constitutes a thread Creating threads general Creating threads Java What happens if synchronization is not used? Assignment Overview What constitutes a thread? Instruction pointer Stack space

More information

Week 12. Streams and File I/O. Overview of Streams and File I/O Text File I/O

Week 12. Streams and File I/O. Overview of Streams and File I/O Text File I/O Week 12 Streams and File I/O Overview of Streams and File I/O Text File I/O 1 I/O Overview I/O = Input/Output In this context it is input to and output from programs Input can be from keyboard or a file

More information

1993: renamed "Java"; use in a browser instead of a microwave : Sun sues Microsoft multiple times over Java

1993: renamed Java; use in a browser instead of a microwave : Sun sues Microsoft multiple times over Java Java history invented mainly by James Gosling ([formerly] Sun Microsystems) 1990: Oak language for embedded systems needs to be reliable, easy to change, retarget efficiency is secondary implemented as

More information

1.Which four options describe the correct default values for array elements of the types indicated?

1.Which four options describe the correct default values for array elements of the types indicated? 1.Which four options describe the correct default values for array elements of the types indicated? 1. int -> 0 2. String -> "null" 3. Dog -> null 4. char -> '\u0000' 5. float -> 0.0f 6. boolean -> true

More information

CISC-124. Passing Parameters. A Java method cannot change the value of any of the arguments passed to its parameters.

CISC-124. Passing Parameters. A Java method cannot change the value of any of the arguments passed to its parameters. CISC-124 20180215 These notes are intended to summarize and clarify some of the topics that have been covered recently in class. The posted code samples also have extensive explanations of the material.

More information

needs to be reliable, easy to change, retarget efficiency is secondary implemented as interpreter, with virtual machine

needs to be reliable, easy to change, retarget efficiency is secondary implemented as interpreter, with virtual machine Java history invented mainly by James Gosling ([formerly] Sun Microsystems) 1990: Oak language for embedded systems needs to be reliable, easy to change, retarget efficiency is secondary implemented as

More information

Java in 21 minutes. Hello world. hello world. exceptions. basic data types. constructors. classes & objects I/O. program structure.

Java in 21 minutes. Hello world. hello world. exceptions. basic data types. constructors. classes & objects I/O. program structure. Java in 21 minutes hello world basic data types classes & objects program structure constructors garbage collection I/O exceptions Strings Hello world import java.io.*; public class hello { public static

More information

Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups:

Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups: Basic Operators Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups: Arithmetic Operators Relational Operators Bitwise Operators

More information

Vendor: Oracle. Exam Code: 1Z Exam Name: Java SE 8 Programmer. Version: Demo

Vendor: Oracle. Exam Code: 1Z Exam Name: Java SE 8 Programmer. Version: Demo Vendor: Oracle Exam Code: 1Z0-808 Exam Name: Java SE 8 Programmer Version: Demo DEMO QUESTION 1 Which of the following data types will allow the following code snippet to compile? A. long B. double C.

More information

Outline. Java Models for variables Types and type checking, type safety Interpretation vs. compilation. Reasoning about code. CSCI 2600 Spring

Outline. Java Models for variables Types and type checking, type safety Interpretation vs. compilation. Reasoning about code. CSCI 2600 Spring Java Outline Java Models for variables Types and type checking, type safety Interpretation vs. compilation Reasoning about code CSCI 2600 Spring 2017 2 Java Java is a successor to a number of languages,

More information

Exceptions Questions https://www.journaldev.com/2167/java-exception-interview-questionsand-answers https://www.baeldung.com/java-exceptions-interview-questions https://javaconceptoftheday.com/java-exception-handling-interviewquestions-and-answers/

More information

bitwise inclusive OR Logical logical AND && logical OR Ternary ternary? : Assignment assignment = += -= *= /= %= &= ^= = <<= >>= >>>=

bitwise inclusive OR Logical logical AND && logical OR Ternary ternary? : Assignment assignment = += -= *= /= %= &= ^= = <<= >>= >>>= Operators in java Operator in java is a symbol that is used to perform operations. For example: +, -, *, / etc. There are many types of operators in java which are given below: Unary Operator, Arithmetic

More information

Chapter 1 Getting Started

Chapter 1 Getting Started Chapter 1 Getting Started The C# class Just like all object oriented programming languages, C# supports the concept of a class. A class is a little like a data structure in that it aggregates different

More information

JAVA BASICS II. Example: FIFO

JAVA BASICS II. Example: FIFO JAVA BASICS II Example: FIFO To show how simple data structures are built without pointers, we ll build a doubly-linked list ListItem class has some user data first refers to that ListItem object at the

More information

More on Exception Handling

More on Exception Handling Chapter 18 More on Exception Handling Lecture slides for: Java Actually: A Comprehensive Primer in Programming Khalid Azim Mughal, Torill Hamre, Rolf W. Rasmussen Cengage Learning, 2008. ISBN: 978-1-844480-933-2

More information

Introduction to Java https://tinyurl.com/y7bvpa9z

Introduction to Java https://tinyurl.com/y7bvpa9z Introduction to Java https://tinyurl.com/y7bvpa9z Eric Newhall - Laurence Meyers Team 2849 Alumni Java Object-Oriented Compiled Garbage-Collected WORA - Write Once, Run Anywhere IDE Integrated Development

More information

Selected Questions from by Nageshwara Rao

Selected Questions from  by Nageshwara Rao Selected Questions from http://way2java.com by Nageshwara Rao Swaminathan J Amrita University swaminathanj@am.amrita.edu November 24, 2016 Swaminathan J (Amrita University) way2java.com (Nageshwara Rao)

More information

CHETTINAD COLLEGE OF ENGINEERING & TECHNOLOGY JAVA

CHETTINAD COLLEGE OF ENGINEERING & TECHNOLOGY JAVA 1. JIT meaning a. java in time b. just in time c. join in time d. none of above CHETTINAD COLLEGE OF ENGINEERING & TECHNOLOGY JAVA 2. After the compilation of the java source code, which file is created

More information

Exam Number/Code : 1Z Exam Name: Name: Java Standard Edition 6. Demo. Version : Programmer Certified Professional Exam.

Exam Number/Code : 1Z Exam Name: Name: Java Standard Edition 6. Demo. Version : Programmer Certified Professional Exam. Exam Number/Code : 1Z0-851 Exam Name: Name: Java Standard Edition 6 Programmer Certified Professional Exam Version : Demo http://it-shiken.jp/ QUESTION 1 public class Threads2 implements Runnable { public

More information

Array. Array Declaration:

Array. Array Declaration: Array Arrays are continuous memory locations having fixed size. Where we require storing multiple data elements under single name, there we can use arrays. Arrays are homogenous in nature. It means and

More information

ECS 140A Midterm 2 November 19, Name (Last, First):, Sign your name:

ECS 140A Midterm 2 November 19, Name (Last, First):, Sign your name: Name (Last, First):, Sign your name: Student ID Number (last six digits, e.g., 12-3456): Grade: /100 points This exam consists of 4 questions on 10 sides, printed on both sides of 5 pages; be sure you

More information

Class definition. complete definition. public public class abstract no instance can be created final class cannot be extended

Class definition. complete definition. public public class abstract no instance can be created final class cannot be extended JAVA Classes Class definition complete definition [public] [abstract] [final] class Name [extends Parent] [impelements ListOfInterfaces] {... // class body public public class abstract no instance can

More information

Software 1 with Java. Initialization. Initialization. Initialization. Pass by Value. Initialization. Recitation No. 11 (Summary)

Software 1 with Java. Initialization. Initialization. Initialization. Pass by Value. Initialization. Recitation No. 11 (Summary) Software 1 with Java Recitation No. 11 (Summary) public class Foo { static int bar; public static void main (String args []) { bar += 1; System.out.println("bar = " + bar); The Does output the code is:

More information

AP COMPUTER SCIENCE JAVA CONCEPTS IV: RESERVED WORDS

AP COMPUTER SCIENCE JAVA CONCEPTS IV: RESERVED WORDS AP COMPUTER SCIENCE JAVA CONCEPTS IV: RESERVED WORDS PAUL L. BAILEY Abstract. This documents amalgamates various descriptions found on the internet, mostly from Oracle or Wikipedia. Very little of this

More information

ECE 461 Fall 2011, Final Exam

ECE 461 Fall 2011, Final Exam ECE 461 Fall 2011, Final Exam DO NOT START WORKING ON THIS UNTIL TOLD TO DO SO. LEAVE IT ON THE DESK. You have until 9:00PM to take this exam. Your exam should have 17 pages total (including this cover

More information

Le L c e t c ur u e e 5 To T p o i p c i s c t o o b e b e co c v o e v r e ed e Exception Handling

Le L c e t c ur u e e 5 To T p o i p c i s c t o o b e b e co c v o e v r e ed e Exception Handling Course Name: Advanced Java Lecture 5 Topics to be covered Exception Handling Exception HandlingHandlingIntroduction An exception is an abnormal condition that arises in a code sequence at run time A Java

More information

APCS Unit 5 Exam. Assuming all four classes have a default constructor, which of the following statements would result in an error from the compiler?

APCS Unit 5 Exam. Assuming all four classes have a default constructor, which of the following statements would result in an error from the compiler? APCS Unit 5 Exam Name 1. Suppose we had a superclass called Fruit. The subclasses of this superclass are Apple, Orange, and Banana. Consider the following reference variable declarations. Fruit f; Banana

More information

Lecture 1: Overview of Java

Lecture 1: Overview of Java Lecture 1: Overview of Java What is java? Developed by Sun Microsystems (James Gosling) A general-purpose object-oriented language Based on C/C++ Designed for easy Web/Internet applications Widespread

More information

Classes and Objects 3/28/2017. How can multiple methods within a Java class read and write the same variable?

Classes and Objects 3/28/2017. How can multiple methods within a Java class read and write the same variable? Peer Instruction 8 Classes and Objects How can multiple methods within a Java class read and write the same variable? A. Allow one method to reference a local variable of the other B. Declare a variable

More information

Exceptions vs. Errors Exceptions vs. RuntimeExceptions try...catch...finally throw and throws

Exceptions vs. Errors Exceptions vs. RuntimeExceptions try...catch...finally throw and throws Lecture 14 Summary Exceptions vs. Errors Exceptions vs. RuntimeExceptions try...catch...finally throw and throws 1 By the end of this lecture, you will be able to differentiate between errors, exceptions,

More information

Java Programming Unit 7. Error Handling. Excep8ons.

Java Programming Unit 7. Error Handling. Excep8ons. Java Programming Unit 7 Error Handling. Excep8ons. Run8me errors An excep8on is an run- 8me error that may stop the execu8on of your program. For example: - someone deleted a file that a program usually

More information

1 Shyam sir JAVA Notes

1 Shyam sir JAVA Notes 1 Shyam sir JAVA Notes 1. What is the most important feature of Java? Java is a platform independent language. 2. What do you mean by platform independence? Platform independence means that we can write

More information

A Third Look At Java. Chapter Seventeen Modern Programming Languages, 2nd ed. 1

A Third Look At Java. Chapter Seventeen Modern Programming Languages, 2nd ed. 1 A Third Look At Java Chapter Seventeen Modern Programming Languages, 2nd ed. 1 A Little Demo public class Test { public static void main(string[] args) { int i = Integer.parseInt(args[0]); int j = Integer.parseInt(args[1]);

More information

Operating Systems CMPSCI 377, Lec 2 Intro to C/C++ Prashant Shenoy University of Massachusetts Amherst

Operating Systems CMPSCI 377, Lec 2 Intro to C/C++ Prashant Shenoy University of Massachusetts Amherst Operating Systems CMPSCI 377, Lec 2 Intro to C/C++ Prashant Shenoy University of Massachusetts Amherst Department of Computer Science Why C? Low-level Direct access to memory WYSIWYG (more or less) Effectively

More information

Final CSE 131B Spring 2004

Final CSE 131B Spring 2004 Login name Signature Name Student ID Final CSE 131B Spring 2004 Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 (25 points) (24 points) (32 points) (24 points) (28 points) (26 points) (22 points)

More information

public class Test { static int age; public static void main (String args []) { age = age + 1; System.out.println("The age is " + age); }

public class Test { static int age; public static void main (String args []) { age = age + 1; System.out.println(The age is  + age); } Question No :1 What is the correct ordering for the import, class and package declarations when found in a Java class? 1. package, import, class 2. class, import, package 3. import, package, class 4. package,

More information

COMP-202 Unit 9: Exceptions

COMP-202 Unit 9: Exceptions COMP-202 Unit 9: Exceptions Announcements - Assignment 4: due Monday April 16th - Assignment 4: tutorial - Final exam tutorial next week 2 Exceptions An exception is an object that describes an unusual

More information

Exceptions, try - catch - finally, throws keyword. JAVA Standard Edition

Exceptions, try - catch - finally, throws keyword. JAVA Standard Edition Exceptions, try - catch - finally, throws keyword JAVA Standard Edition Java - Exceptions An exception (or exceptional event) is a problem that arises during the execution of a program. When an Exception

More information

1. Find the output of following java program. class MainClass { public static void main (String arg[])

1. Find the output of following java program. class MainClass { public static void main (String arg[]) 1. Find the output of following java program. public static void main(string arg[]) int arr[][]=4,3,2,1; int i,j; for(i=1;i>-1;i--) for(j=1;j>-1;j--) System.out.print(arr[i][j]); 1234 The above java program

More information

COMP-202 Unit 9: Exceptions

COMP-202 Unit 9: Exceptions COMP-202 Unit 9: Exceptions Course Evaluations Please do these. -Fast to do -Used to improve course for future. (Winter 2011 had 6 assignments reduced to 4 based on feedback!) 2 Avoiding errors So far,

More information

CSC 1214: Object-Oriented Programming

CSC 1214: Object-Oriented Programming CSC 1214: Object-Oriented Programming J. Kizito Makerere University e-mail: jkizito@cis.mak.ac.ug www: http://serval.ug/~jona materials: http://serval.ug/~jona/materials/csc1214 e-learning environment:

More information

Lecture 4: Outline. Arrays. I. Pointers II. III. Pointer arithmetic IV. Strings

Lecture 4: Outline. Arrays. I. Pointers II. III. Pointer arithmetic IV. Strings Lecture 4: Outline I. Pointers A. Accessing data objects using pointers B. Type casting with pointers C. Difference with Java references D. Pointer pitfalls E. Use case II. Arrays A. Representation in

More information

Notes on Java Programming IST JAV 2012 S. Frénot

Notes on Java Programming IST JAV 2012 S. Frénot I) Refactoring The next code contains three classes : public abstract class Triangle{ protected int sidea,sideb,sidec; Notes on Java Programming IST JAV 2012 S. Frénot public Triangle(int a, int b, int

More information

File Operations in Java. File handling in java enables to read data from and write data to files

File Operations in Java. File handling in java enables to read data from and write data to files Description Java Basics File Operations in Java File handling in java enables to read data from and write data to files along with other file manipulation tasks. File operations are present in java.io

More information

Exceptions and I/O: sections Introductory Programming. Errors in programs. Exceptions

Exceptions and I/O: sections Introductory Programming. Errors in programs. Exceptions Introductory Programming Exceptions and I/O: sections 80 83 Anne Haxthausen a IMM, DTU 1 Exceptions (section 80) 2 Input and output (I/O) (sections 81-83) a Parts of this material are inspired by/originate

More information

Introductory Programming Exceptions and I/O: sections

Introductory Programming Exceptions and I/O: sections Introductory Programming Exceptions and I/O: sections 80 83 Anne Haxthausen a IMM, DTU 1 Exceptions (section 80) 2 Input and output (I/O) (sections 81-83) a Parts of this material are inspired by/originate

More information

ECE Fall 20l2, Second Exam

ECE Fall 20l2, Second Exam ECE 30862 Fall 20l2, Second Exam DO NOT START WORKING ON THIS UNTIL TOLD TO DO SO. LEAVE IT ON THE DESK. You have until 12:20 to take this exam. Your exam should have 16 pages total (including this cover

More information

1.00 Lecture 4. Promotion

1.00 Lecture 4. Promotion 1.00 Lecture 4 Data Types, Operators Reading for next time: Big Java: sections 6.1-6.4 Promotion increasing capacity Data Type Allowed Promotions double None float double long float,double int long,float,double

More information

School of Informatics, University of Edinburgh

School of Informatics, University of Edinburgh CS1Ah Lecture Note 29 Streams and Exceptions We saw back in Lecture Note 9 how to design and implement our own Java classes. An object such as a Student4 object contains related fields such as surname,

More information

Argument Passing All primitive data types (int etc.) are passed by value and all reference types (arrays, strings, objects) are used through refs.

Argument Passing All primitive data types (int etc.) are passed by value and all reference types (arrays, strings, objects) are used through refs. Local Variable Initialization Unlike instance vars, local vars must be initialized before they can be used. Eg. void mymethod() { int foo = 42; int bar; bar = bar + 1; //compile error bar = 99; bar = bar

More information

IBD Intergiciels et Bases de Données

IBD Intergiciels et Bases de Données IBD Intergiciels et Bases de Données RMI-based distributed systems Fabien Gaud, Fabien.Gaud@inrialpes.fr Overview of lectures and practical work Lectures Introduction to distributed systems and middleware

More information

Introduction to Java

Introduction to Java Introduction to Java Module 1: Getting started, Java Basics 22/01/2010 Prepared by Chris Panayiotou for EPL 233 1 Lab Objectives o Objective: Learn how to write, compile and execute HelloWorld.java Learn

More information

BBM 102 Introduction to Programming II Spring Exceptions

BBM 102 Introduction to Programming II Spring Exceptions BBM 102 Introduction to Programming II Spring 2018 Exceptions 1 Today What is an exception? What is exception handling? Keywords of exception handling try catch finally Throwing exceptions throw Custom

More information

Advanced Java Concepts Unit 2: Linked Lists.

Advanced Java Concepts Unit 2: Linked Lists. Advanced Java Concepts Unit 2: Linked Lists. The List interface defines the structure of a linear collection. Here are some of its methods. boolean add( E element ) Appends the element to the end of the

More information

An overview of Java, Data types and variables

An overview of Java, Data types and variables An overview of Java, Data types and variables Lecture 2 from (UNIT IV) Prepared by Mrs. K.M. Sanghavi 1 2 Hello World // HelloWorld.java: Hello World program import java.lang.*; class HelloWorld { public

More information

(A) 99 (B) 100 (C) 101 (D) 100 initial integers plus any additional integers required during program execution

(A) 99 (B) 100 (C) 101 (D) 100 initial integers plus any additional integers required during program execution Ch 5 Arrays Multiple Choice 01. An array is a (A) (B) (C) (D) data structure with one, or more, elements of the same type. data structure with LIFO access. data structure, which allows transfer between

More information

Access and Non access Modifiers in Core Java Core Java Tutorial

Access and Non access Modifiers in Core Java Core Java Tutorial Access and Non access Modifiers in Core Java Core Java Tutorial Modifiers in Java Modifiers are keywords that are added to change meaning of a definition. In Java, modifiers are catagorized into two types,

More information

G51PGP Programming Paradigms. Lecture 009 Concurrency, exceptions

G51PGP Programming Paradigms. Lecture 009 Concurrency, exceptions G51PGP Programming Paradigms Lecture 009 Concurrency, exceptions 1 Reminder subtype polymorphism public class TestAnimals public static void main(string[] args) Animal[] animals = new Animal[6]; animals[0]

More information

Rules and syntax for inheritance. The boring stuff

Rules and syntax for inheritance. The boring stuff Rules and syntax for inheritance The boring stuff The compiler adds a call to super() Unless you explicitly call the constructor of the superclass, using super(), the compiler will add such a call for

More information

5) Attacker causes damage Different to gaining control. For example, the attacker might quit after gaining control.

5) Attacker causes damage Different to gaining control. For example, the attacker might quit after gaining control. Feb 23, 2009 CSE, 409/509 Mitigation of Bugs, Life of an exploit 1) Bug inserted into code 2) Bug passes testing 3) Attacker triggers bug 4) The Attacker gains control of the program 5) Attacker causes

More information

Class, Variable, Constructor, Object, Method Questions

Class, Variable, Constructor, Object, Method Questions Class, Variable, Constructor, Object, Method Questions http://www.wideskills.com/java-interview-questions/java-classes-andobjects-interview-questions https://www.careerride.com/java-objects-classes-methods.aspx

More information

Java Primer. CITS2200 Data Structures and Algorithms. Topic 2

Java Primer. CITS2200 Data Structures and Algorithms. Topic 2 CITS2200 Data Structures and Algorithms Topic 2 Java Primer Review of Java basics Primitive vs Reference Types Classes and Objects Class Hierarchies Interfaces Exceptions Reading: Lambert and Osborne,

More information

More on Exception Handling

More on Exception Handling Chapter 18 More on Exception Handling Lecture slides for: Java Actually: A Comprehensive Primer in Programming Khalid Azim Mughal, Torill Hamre, Rolf W. Rasmussen Cengage Learning, 2008. ISBN: 978-1-844480-933-2

More information

CSE 431S Type Checking. Washington University Spring 2013

CSE 431S Type Checking. Washington University Spring 2013 CSE 431S Type Checking Washington University Spring 2013 Type Checking When are types checked? Statically at compile time Compiler does type checking during compilation Ideally eliminate runtime checks

More information

C16b: Exception Handling

C16b: Exception Handling CISC 3120 C16b: Exception Handling Hui Chen Department of Computer & Information Science CUNY Brooklyn College 3/28/2018 CUNY Brooklyn College 1 Outline Exceptions Catch and handle exceptions (try/catch)

More information

Lara Technologies Special-Six Test

Lara Technologies Special-Six Test Flow control Part-1 Q: 01 Given: 10. public class Bar 11. static void foo( int... x ) 12. // insert code here 13. 14. Which two code fragments, inserted independently at line 12, will allow the class to

More information

JAVA RMI. Remote Method Invocation

JAVA RMI. Remote Method Invocation 1 JAVA RMI Remote Method Invocation 2 Overview Java RMI is a mechanism that allows one to invoke a method on an object that exists in another address space. The other address space could be: On the same

More information

JAVA OPERATORS GENERAL

JAVA OPERATORS GENERAL JAVA OPERATORS GENERAL Java provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups: Arithmetic Operators Relational Operators Bitwise Operators

More information

CMSC131. Exceptions and Exception Handling. When things go "wrong" in a program, what should happen.

CMSC131. Exceptions and Exception Handling. When things go wrong in a program, what should happen. CMSC131 Exceptions and Exception Handling When things go "wrong" in a program, what should happen. Go forward as if nothing is wrong? Try to handle what's going wrong? Pretend nothing bad happened? Crash

More information

Java Language Features

Java Language Features Java Language Features References: Object-Oriented Development Using Java, Xiaoping Jia Internet Course notes by E.Burris Computing Fundamentals with Java, by Rick Mercer Beginning Java Objects - From

More information

Binghamton University. CS-140 Fall Dynamic Types

Binghamton University. CS-140 Fall Dynamic Types Dynamic Types 1 Assignment to a subtype If public Duck extends Bird { Then, you may code:. } Bird bref; Duck quack = new Duck(); bref = quack; A subtype may be assigned where the supertype is expected

More information

Kickstart Intro to Java Part I

Kickstart Intro to Java Part I Kickstart Intro to Java Part I COMP346/5461 - Operating Systems Revision 1.6 February 9, 2004 1 Topics Me, Myself, and I Why Java 1.2.*? Setting Up the Environment Buzz about Java Java vs. C++ Basic Java

More information

Chapter 12 Exception Handling

Chapter 12 Exception Handling Chapter 12 Exception Handling 1 Motivations Goal: Robust code. When a program runs into a runtime error, the program terminates abnormally. How can you handle the runtime error so that the program can

More information

BIT Java Programming. Sem 1 Session 2011/12. Chapter 2 JAVA. basic

BIT Java Programming. Sem 1 Session 2011/12. Chapter 2 JAVA. basic BIT 3383 Java Programming Sem 1 Session 2011/12 Chapter 2 JAVA basic Objective: After this lesson, you should be able to: declare, initialize and use variables according to Java programming language guidelines

More information

For more details on SUN Certifications, visit

For more details on SUN Certifications, visit Exception Handling For more details on SUN Certifications, visit http://sunjavasnips.blogspot.com/ Q: 01 Given: 11. public static void parse(string str) { 12. try { 13. float f = Float.parseFloat(str);

More information

Here is a hierarchy of classes to deal with Input and Output streams.

Here is a hierarchy of classes to deal with Input and Output streams. PART 15 15. Files and I/O 15.1 Reading and Writing Files A stream can be defined as a sequence of data. The InputStream is used to read data from a source and the OutputStream is used for writing data

More information

Input-Output and Exception Handling

Input-Output and Exception Handling Software and Programming I Input-Output and Exception Handling Roman Kontchakov / Carsten Fuhs Birkbeck, University of London Outline Reading and writing text files Exceptions The try block catch and finally

More information

Introduce C# as Object Oriented programming language. Explain, tokens,

Introduce C# as Object Oriented programming language. Explain, tokens, Module 2 98 Assignment 1 Introduce C# as Object Oriented programming language. Explain, tokens, lexicals and control flow constructs. 99 The C# Family Tree C Platform Independence C++ Object Orientation

More information

Chapter 10. Exception Handling. Java Actually: A Comprehensive Primer in Programming

Chapter 10. Exception Handling. Java Actually: A Comprehensive Primer in Programming Chapter 10 Exception Handling Lecture slides for: Java Actually: A Comprehensive Primer in Programming Khalid Azim Mughal, Torill Hamre, Rolf W. Rasmussen Cengage Learning, 2008. ISBN: 978-1-844480-933-2

More information

Modern Programming Languages. Lecture Java Programming Language. An Introduction

Modern Programming Languages. Lecture Java Programming Language. An Introduction Modern Programming Languages Lecture 27-30 Java Programming Language An Introduction 107 Java was developed at Sun in the early 1990s and is based on C++. It looks very similar to C++ but it is significantly

More information

CA31-1K DIS. Pointers. TA: You Lu

CA31-1K DIS. Pointers. TA: You Lu CA31-1K DIS Pointers TA: You Lu Pointers Recall that while we think of variables by their names like: int numbers; Computer likes to think of variables by their memory address: 0012FED4 A pointer is a

More information

Exception Handling. Run-time Errors. Methods Failure. Sometimes when the computer tries to execute a statement something goes wrong:

Exception Handling. Run-time Errors. Methods Failure. Sometimes when the computer tries to execute a statement something goes wrong: Exception Handling Run-time errors The exception concept Throwing exceptions Handling exceptions Declaring exceptions Creating your own exception 22 November 2007 Ariel Shamir 1 Run-time Errors Sometimes

More information

CS 231 Data Structures and Algorithms, Fall 2016

CS 231 Data Structures and Algorithms, Fall 2016 CS 231 Data Structures and Algorithms, Fall 2016 Dr. Bruce A. Maxwell Department of Computer Science Colby College Course Description Focuses on the common structures used to store data and the standard

More information

Oracle 1Z Java SE 8 Programmer I. Download Full Version :

Oracle 1Z Java SE 8 Programmer I. Download Full Version : Oracle 1Z0-808 Java SE 8 Programmer I Download Full Version : https://killexams.com/pass4sure/exam-detail/1z0-808 QUESTION: 121 And the commands: Javac Jump.java Java Jump crazy elephant is always What

More information

Page 2 Page 3 Page 4 Page 5 Page 7 Total

Page 2 Page 3 Page 4 Page 5 Page 7 Total Page 2 Page 3 Page 4 Page 5 Page 7 Total LAST NAME FIRST NAME STUDENT NUMBER A COMP 249 Midterm Test Winter 2016 Section QQ Duration: 75 minutes No calculators or additional resources Write only on the

More information