Cse 15L Final

Front 1

T/F: Science never proves theories, only disproves them

Back 1

True

Front 2

T/F: When debugging, it is a best practice to make one change at a time and keep a record of the changes

Back 2

True

Front 3

T/F: Shell scripts are not executable by default

Back 3

True

Front 4

T/F: In a shell script, line starting with #! are comments

Back 4

False

Front 5

T/F: In Unix, the command line arguments passed to a shell script are stored in positional parametrs

Back 5

Tru

Front 6

T/F: A logger cannot have multiple handlers

Back 6

False

Front 7

T/F: It is a good practice to download the latest version of the software before you report a bug

Back 7

True

Front 8

T/F: A shell acts as an interface between the user and the system

Back 8

True

Front 9

T/F: As a command interpreter, the shell sends the commands to the kernel for execution

Back 9

True

Front 10

T/F: A directory is a specialized form of file that maintains a list of all files in it.

Back 10

True

Front 11

T/F: Unit testing is the testing of the whole class as a unit

Back 11

False - method

Front 12

T/F: JUnit is a unit testing framework of the Java Programming Language

Back 12

True

Front 13

T/F: Debugging is not algorithmic

Back 13

True

Front 14

T/F: In test-driven development, tests are written before the software to be tested is written

Back 14

True

Front 15

T/F: It is usually feasible to test all possible values of arguments to a method

Back 15

False

Front 16

T/F: stdout should be used for unusual output from your program, such as error reporting

Back 16

False - stderr

Front 17

T/F: In a Makefile, every target line must begin with a tab

Back 17

False - action line

Front 18

T/F: In debugging, reproducing the problem comes before fixing the problem

Back 18

True

Front 19

T/F: If all your unit tests pass, that means the software being tested has no bugs

Back 19

False

Front 20

T/F: A software version management repository holds a master copy of only text/html code

Back 20

False - other artifacts as well

Front 21

T/F: Making changes to a software repository means editing, adding and deleting files

Back 21

True

Front 22

T/F: IDE stands for "integrated development environment"

Back 22

True

Front 23

T/F: Eclipse does not allow you to have multiple workspaces

Back 23

False - you can have multiple workspaces

Front 24

T/F: In test-driven development, you must understand the specification of what the software you are testing is supposed to do

Back 24

True

Front 25

T/F: In Unix, executing programs have unique process identifiers

Back 25

True

Front 26

T/F: A Unix pipe is a way to send the output of one command to the input of another

Back 26

True

Front 27

T/F: As a login script, .profile runs each time a Unix shell is started

Back 27

True

Front 28

T/F: The Makefile contains rules which tell make what to do

Back 28

True

Front 29

T/F: If a target in a Makefile names a file that is older than the files is depends on, then the actions in that rule will not be performed

Back 29

False

Front 30

List three components of a good development environment for a mid-sized project team

Back 30

- A source code version control system

- A fully automated testing system

- A fully automated compile/build system

- Frequent built/integrate/distribute policy

Front 31

List two cons of test-driven development

Back 31

-Doesn't tell full software

-Takes a long time to write all those tests

Front 32

How is the command

$cat file2

different from

$cat > file2 and $cat >> file2 ?

Back 32

cat file2 displays the contents of file 2, where > and >> redirect the input to file2

Front 33

What is redirection in Unix? Provide an example command that uses redirection.

Back 33

Directing the flow of data to the file or from the file for input or output

Ex: ls > wc

Front 34

What Unix command is used for changing file access permissions?

Back 34

chmod

Front 35

What does the command "$ls | wc -l > file1" do?

Back 35

ls becomes the input to wc which counts the number of lines it receives as input and instead of displaying this count, the value is stored in file1

Front 36

What is a pipe and give an example?

Back 36

A pipe is two or more commands separated by pipe char '|'. That tells the shell to arrange for the output of the preceding command to be passed as input the following command.

Ex: ls -l | pr

The output for a command ls is the standard input of pr. This is called a pipeline.

Front 37

One can change the access permissions on a file calld 'temp.txt' to readable, writeable and executable only by the file owner.

Back 37

chmod 700 temp.txt

Front 38

Construct the pipe to execute the following job.

"Output of ls should be displayed on the screen and from this output the lines containing the word 'poem' should be counted and the count should be stored in a file."

Back 38

ls | grep poem | wc -l > out.txt

Front 39

The command

$cat par.3 par.4 par.5 >> report

a. displays contents of the files par.3, part.4 and par.4 on the command line and overwrites the file report with the output

b. appends the file report with the contents of par.3, par.4, and par.5

c. displays contents of the files par.3, par.4 and par.5 on the command line and appends the file report with the output

d. overwrites the file report with the contents of the file par.5

Back 39

b. appends the file report with the contents of par.3, par.4, and par.5

Front 40

The positional parameter $0 refers to:

a. Total number of arguments

b. Command or the script name

c. First argument respectively

d. All the command line arguments starting from $1

Back 40

b. Command or the script name

Front 41

Define a shell array called CLASS with elements "Altintas", "CSE15L", "Fall 2013" in the given order. Display the second element with the Unix command.

Back 41

[

CLASS[0]="Altintas"

CLASS[1]="CSE15L"

CLASS[2]="Fall 2013"

echo "Second element: ${CLASS[1]}"

]

Front 42

Complete the following sentence:

"______ command displays the current working directory in Unix shell."

Back 42

pwd

Front 43

List three tools for diagnostic output

Back 43

-Standard output and standard error

-Java logging framework

-Java assertions

-Java profiling framework

-Debuggers

Front 44

List three pieces of information provided by Java logging API

Back 44

-The origin of a log entry (which application, which class, which method, etc)

-The content of the log entry

-The level of importance of the log entry

Front 45

Name steps in debugging in order

Back 45

1. Understand the system

2. Identify the problem

3. Reproduce the problem

4. Diagnose the cause of the problem

5. Fix the problem

6. Reflect and learn from this problem, and this fix

Front 46

The binary output from hprof can be opened using ________.

Back 46

jhat

Front 47

List two things a bug reporter should read or check to report a good bug

Back 47

-Make sure software is up to date

-Search the bug repository to see whether your bug has already been reported

Front 48

What is the difference between the heap and cpu options in hprof?

Back 48

Heap option helps you perform analysis of memory usage (where memory was allocated)

CPU option lets you understand processor usage (where CPU spent more time than others)

Front 49

Using the cpu option in hprof with value as _______ can significantly slow down progress

Back 49

times

Front 50

Write a Unix command that displays the contents of folder "Q1" in long form including the directory entires whose names begin with a dot(.)

Back 50

ls -la Q1

Front 51

List three common Unix shells

Back 51

bash, ksh, tcsh

Front 52

Write a command to make the file "Q3.txt" in the current directory read-only.

Back 52

chmod 444 Q3.txt

Front 53

Absolute path in Unix paths start at:

a. users

b. bin

c. home

d. root

Back 53

d. root

Front 54

Relative to the working directory, dot dot (..) refers to:

a. current working directory

b. home

c. root

d. a level above

Back 54

d. a level above

Front 55

List the names of the two files that a shell automatically opens when it starts up.

Back 55

.bashrc, .profile

Front 56

Write a command that redirects the contents of standard input to an output file called 'temp.txt'

Back 56

cat > temp.txt

Front 57

Write a filtering command using Unix pipes to search for occurrences of the word 'time ' in the manual page for Unix command called "time".

Back 57

man time | grep time

Front 58

What is the function of the Unix environment variable "PATH"?

Back 58

The PATH environment variable is a colon-delimited list of directories that your shell searches through when you enter a command.

Front 59

List two pros and two cons of unit testing

Back 59

Pros:

-Increased productivity

-Results in modular and extensible software

-Leads to better code functionality

-Concise goal-driven code

Cons:

-Does not test full software

-Requires team buy-in

-Same developer coding and testing a feature

-Can consume too much time

Front 60

Which file does make look for in the current working directory?

Back 60

Makefile

Front 61

For this problem, consider this Makefile:

A.class: A.java

javac A.java

B.class: A.class B.java

javac B.java

C.class: B.class A.class C.java

javac C.java

all: C.class B.class A.classa.

Suppose ls -l produces this output:

-rw-rw-r-- 1 u1 lec 150 May 7 13:16 A.java

-rw-rw-r-- 1 u1 lec 81 May 7 13:25 B.java

-rw-rw-r-- 1 u1 lec 189 May 7 13:20 C.java

-rw-rw-r-- 1 u1 lec 168 May 7 13:00 Makefile

(a) Now running “make all” will cause what command(s) to be executed? List them.

(b) Suppose ls -l produces this output:

-rw-rw-r-- 1 u1 lec 356 May 7 13:50 A.class

-rw-rw-r-- 1 u1 lec 150 May 7 13:16 A.java

-rw-rw-r-- 1 u1 lec 251 May 7 13:50 B.class

-rw-rw-r-- 1 u1 lec 69 May 7 13:25 B.java

-rw-rw-r-- 1 u1 lec 532 May 7 13:50 C.class

-rw-rw-r-- 1 u1 lec 189 May 7 13:55 C.java

-rw-rw-r-- 1 u1 lec 168 May 7 13:00 Makefile

Now running make all will cause what command(s) to be executed? List them.

Back 61

a) javac A.java

javac B.java

javac C.java

b) javac C.java

Front 62

To make the _________, first make all its _________, then perform all the _______.

Back 62

target, dependencies, actions

Front 63

List two problems that can arise in non-version controlled software when there is only one individual involved in the software development process.

Back 63

1) No way to go back to previous version once saved (revert)

2) Cannot provide stable version releases, as in cannot "freeze" one version for deployment and continue working on a new version

Front 64

Put the following steps in order within an version control workflow:

-makes changes

-update

-commit

-resolve conflicts

Back 64

1) update

2) make changes

3) update

4) resolve conflicts

5) commit

Front 65

A string enclosed in back quotes(") in a Unix shell script is treated as a ___________ and the shell attempts to execute it.

Back 65

command

Front 66

Complete the following shell script.

#!/bin/sh

echo Total number of inputs: _______

echo First input: _______

echo Second input: ________

Back 66

1) $#

2) $1

3) $2

Front 67

Square brackets ([ ]) in a Unix shell script is an alias for the _____ command.

Back 67

test

Front 68

a) Draw the project directory structure after you run "ant compile"

Back 68

Front 69

b) What does the doc target accomplish?

c) Which target will run if you only run "ant" on command for this build file?

d) What targets does the doc target depend on?

Back 69

b) generate documentation

c) doc

d) compile