Re: Convert C++ Code to Java
What part of the C++ code don't you understand?
Re: Convert C++ Code to Java
Quote:
Originally Posted by
ForgottenLaw
I have an assignment in converting this C++ Code to Java.
Your assignment seems to come from here as someone's solution to an exercise in Absolute C++ by Savitch.
http://www.sr2jr.com/textbook-soluti...es-and-classes
Maybe it was your Java instructor who posted it there?
Anyway, why not use a free C++ to Java converter? There are quite a few on the internet.
Quote:
I also need to study the difference in the implementation of the code in C++ and Java
The C++ program adheres to the procedural programming paradigm. That means a straight conversion to Java will use the static keyword extensively. However, overusing static is considered bad Java. So, except for the syntax, the C++ and Java versions will be identical. But they will be perceived differently by each programming community - okay in C++, not okay in Java.
Re: Convert C++ Code to Java
As you have the original exercise requirements, I'd suggest you forget the C++ code and code your own version direct in Java. You'll learn more.
Re: Convert C++ Code to Java
It's not even that good C++ code... Perhaps 'better' C++:
Code:
#include <iostream>
#include <iomanip>
#include <string>
struct StudentGrade {
unsigned quiz1 {};
unsigned quiz2 {};
unsigned midterm {};
unsigned final{};
unsigned total {};
std::string firstName;
std::string lastName;
double percent {}, avg {};
char letterGrade {};
double q1 {};
double q2 {};
double m {};
double f {};
};
StudentGrade getData();
void setLetterGrade(StudentGrade&);
void format(int);
void output(const StudentGrade&);
constexpr double Q_PERCENT { 12.5 };
constexpr double M_PERCENT { 25.0 };
constexpr double F_PERCENT { 50.0 };
constexpr double Q_SCORE { 10 };
constexpr double E_SCORE { 100 };
constexpr auto tScore { Q_SCORE * 2 + E_SCORE * 2 };
constexpr auto tPercent { Q_PERCENT * 2 + M_PERCENT + F_PERCENT };
#define W std::setw(17)
#define Y std::setw(10)
int main() {
char run_again {};
do {
output(getData());
std::cout << "Would you like to try again for another student? ([Y]es/[N]o) : ";
std::cin >> run_again;
} while ((run_again == 'y') || (run_again == 'Y'));
}
void output(const StudentGrade& g) {
format(1);
std::cout << "\n\nHere are the results for " << g.firstName << " " << g.lastName << ".\n";
std::cout << Y << "TEST" << Y << "TEST" << Y << "MAX" << W << "GRADE SCORE"
<< W << "MAXIMUM SCORE" << '\n';
std::cout << Y << "PERIOD" << Y << "SCORE" << Y << "SCORE" << W << "DISTRIBUTION"
<< W << "DISTRIBUTION" << "\n\n";
std::cout << Y << "Quiz 1" << Y << g.quiz1 << Y << Q_SCORE << W << g.q1 << "%"
<< W << Q_PERCENT << "%\n";
std::cout << Y << "Quiz 2" << Y << g.quiz2 << Y << Q_SCORE << W << g.q2 << "%"
<< W << Q_PERCENT << "%\n";
std::cout << Y << "Midterm" << Y << g.midterm << Y << E_SCORE << W << g.m << "%"
<< W << M_PERCENT << "%\n";
std::cout << Y << "Final" << Y << g.final << Y << E_SCORE << W << g.f << "%"
<< W << F_PERCENT << "%\n";
std::cout << Y << "_________________________________________________ ______________________\n";
std::cout << Y << "TOTAL" << Y << g.total << Y << tScore << W << g.percent << "%"
<< W << tPercent << "%\n";
std::cout << Y << "Average" << Y << (double(g.total) / tScore * tPercent) << "%\n";
std::cout << Y << "Grade: " << Y << g.letterGrade << "\n\n\n";
}
StudentGrade getData() {
StudentGrade g;
std::cout << "Enter the student's first name: ";
std::cin >> g.firstName;
std::cout << "Enter the student's last name: ";
std::cin >> g.lastName;
std::cout << "Enter Quiz 1 score (maximum is 10): ";
std::cin >> g.quiz1;
std::cout << "Enter Quiz 2 score (maximum is 10): ";
std::cin >> g.quiz2;
std::cout << "Enter Midterm score (maximum is 100): ";
std::cin >> g.midterm;
std::cout << "Enter Final score (maximum is 100): ";
std::cin >> g.final;
g.quiz1 = g.quiz1 > 10 ? 10 : g.quiz1;
g.quiz2 = g.quiz2 > 10 ? 10 : g.quiz2;
g.midterm = g.midterm > 100 ? 100 : g.midterm;
g.final = g.final > 100 ? 100 : g.final;
g.q1 = g.quiz1 / Q_SCORE * Q_PERCENT;
g.q2 = g.quiz2 / Q_SCORE * Q_PERCENT;
g.m = g.midterm / E_SCORE * M_PERCENT;
g.f = g.midterm / E_SCORE * F_PERCENT;
g.total = g.quiz1 + g.quiz2 + g.midterm + g.final;
g.percent = g.q1 + g.q2 + g.m + g.f;
setLetterGrade(g);
return g;
}
void setLetterGrade(StudentGrade& g)
{
if (g.percent >= 90.0)
g.letterGrade = 'A';
else if (g.percent >= 80.0)
g.letterGrade = 'B';
else if (g.percent >= 70.0)
g.letterGrade = 'C';
else if (g.percent >= 60.0)
g.letterGrade = 'D';
else
g.letterGrade = 'F';
}
void format(int n)
{
std::cout.setf(std::ios::fixed);
std::cout.setf(std::ios::showpoint);
std::cout.precision(n);
}
[Excluding std::format from C++20]
Re: Convert C++ Code to Java
Quote:
Originally Posted by
2kaud
It's not even that good C++ code...
I agree. The code the OP posted looks like written by a C++ newbie, which it probably is, considering where it originates (as someone's solution to a textbook exercise). No programming language educator with self-respect would "borrow" such code and reuse it in an assignment.
I tried the first free C++ to Java converter I found on the internet on your code.
https://c-to-java-converter-free-edi....informer.com/
Here is the result:
Code:
public class GlobalMembers
{
public static StudentGrade getData()
{
StudentGrade g = new StudentGrade();
System.out.print("Enter the student's first name: ");
g.firstName = ConsoleInput.readToWhiteSpace(true);
System.out.print("Enter the student's last name: ");
g.lastName = ConsoleInput.readToWhiteSpace(true);
System.out.print("Enter Quiz 1 score (maximum is 10): ");
g.quiz1 = Integer.parseInt(ConsoleInput.readToWhiteSpace(true));
System.out.print("Enter Quiz 2 score (maximum is 10): ");
g.quiz2 = Integer.parseInt(ConsoleInput.readToWhiteSpace(true));
System.out.print("Enter Midterm score (maximum is 100): ");
g.midterm = Integer.parseInt(ConsoleInput.readToWhiteSpace(true));
System.out.print("Enter Final score (maximum is 100): ");
g.final = Integer.parseInt(ConsoleInput.readToWhiteSpace(true));
g.quiz1 = g.quiz1 > 10 ? 10 : g.quiz1;
g.quiz2 = g.quiz2 > 10 ? 10 : g.quiz2;
g.midterm = g.midterm > 100 ? 100 : g.midterm;
g.final = g.final > 100 ? 100 : g.final;
g.q1 = g.quiz1 / Q_SCORE * Q_PERCENT;
g.q2 = g.quiz2 / Q_SCORE * Q_PERCENT;
g.m = g.midterm / E_SCORE * M_PERCENT;
g.f = g.midterm / E_SCORE * F_PERCENT;
g.total = g.quiz1 + g.quiz2 + g.midterm + g.final;
g.percent = g.q1 + g.q2 + g.m + g.f;
setLetterGrade(g);
return g;
}
public static void setLetterGrade(StudentGrade g)
{
if (g.percent >= 90.0)
{
g.letterGrade = (byte)'A';
}
else if (g.percent >= 80.0)
{
g.letterGrade = (byte)'B';
}
else if (g.percent >= 70.0)
{
g.letterGrade = (byte)'C';
}
else if (g.percent >= 60.0)
{
g.letterGrade = (byte)'D';
}
else
{
g.letterGrade = (byte)'F';
}
}
public static void format(int n)
{
//C++ TO JAVA CONVERTER TODO TASK: The cout 'showpoint' manipulator is not converted by C++ to Java Converter:
//ORIGINAL LINE: std::cout.setf(std::ios::showpoint);
}
public static void output(StudentGrade g)
{
format(1);
System.out.print("\n\nHere are the results for ");
System.out.print(g.firstName);
System.out.print(" ");
System.out.print(g.lastName);
System.out.print(".\n");
System.out.printf("%10d", "TEST");
System.out.printf("%10d", "TEST");
System.out.printf("%10d", "MAX");
System.out.printf("%17d", "GRADE SCORE");
System.out.printf("%17d", "MAXIMUM SCORE");
System.out.printf("%d", '\n');
System.out.printf("%10d", "PERIOD");
System.out.printf("%10d", "SCORE");
System.out.printf("%10d", "SCORE");
System.out.printf("%17d", "DISTRIBUTION");
System.out.printf("%17d", "DISTRIBUTION");
System.out.printf("%d", "\n\n");
System.out.printf("%10d", "Quiz 1");
System.out.printf("%10d", g.quiz1);
System.out.printf("%10d", Q_SCORE);
System.out.printf("%17d", g.q1);
System.out.printf("%d", "%");
System.out.printf("%17d", Q_PERCENT);
System.out.printf("%d", "%\n");
System.out.printf("%10d", "Quiz 2");
System.out.printf("%10d", g.quiz2);
System.out.printf("%10d", Q_SCORE);
System.out.printf("%17d", g.q2);
System.out.printf("%d", "%");
System.out.printf("%17d", Q_PERCENT);
System.out.printf("%d", "%\n");
System.out.printf("%10d", "Midterm");
System.out.printf("%10d", g.midterm);
System.out.printf("%10d", E_SCORE);
System.out.printf("%17d", g.m);
System.out.printf("%d", "%");
System.out.printf("%17d", M_PERCENT);
System.out.printf("%d", "%\n");
System.out.printf("%10d", "Final");
System.out.printf("%10d", g.final);
System.out.printf("%10d", E_SCORE);
System.out.printf("%17d", g.f);
System.out.printf("%d", "%");
System.out.printf("%17d", F_PERCENT);
System.out.printf("%d", "%\n");
System.out.printf("%10d", "_________________________________________________ ______________________\n");
System.out.printf("%10d", "TOTAL");
System.out.printf("%10d", g.total);
System.out.printf("%10d", tScore);
System.out.printf("%17d", g.percent);
System.out.printf("%d", "%");
System.out.printf("%17d", tPercent);
System.out.printf("%d", "%\n");
System.out.printf("%10d", "Average");
System.out.printf("%10d", ((double)g.total / tScore * tPercent));
System.out.printf("%d", "%\n");
System.out.printf("%10d", "Grade: ");
System.out.printf("%10d", g.letterGrade);
System.out.printf("%d", "\n\n\n");
}
public static final double Q_PERCENT = 12.5;
public static final double M_PERCENT = 25.0;
public static final double F_PERCENT = 50.0;
public static final double Q_SCORE = 10;
public static final double E_SCORE = 100;
public static final auto tScore = new auto(Q_SCORE * 2 + E_SCORE * 2);
public static final auto tPercent = new auto(Q_PERCENT * 2 + M_PERCENT + F_PERCENT);
//C++ TO JAVA CONVERTER NOTE: The following #define macro was replaced in-line:
//ORIGINAL LINE: #define W std::setw(17)
//C++ TO JAVA CONVERTER NOTE: The following #define macro was replaced in-line:
//ORIGINAL LINE: #define Y std::setw(10)
public static int Main()
{
byte run_again = 0;
do
{
output(getData());
System.out.print("Would you like to try again for another student? ([Y]es/[N]o) : ");
run_again = Byte.parseByte(ConsoleInput.readToWhiteSpace(true));
} while ((run_again == 'y') || (run_again == 'Y'));
}
}
public class StudentGrade
{
public int quiz1 = 0;
public int quiz2 = 0;
public int midterm = 0;
public int final = 0;
public int total = 0;
public String firstName;
public String lastName;
public double percent = 0;
public double avg = 0;
public byte letterGrade = 0;
public double q1 = 0;
public double q2 = 0;
public double m = 0;
public double f = 0;
}
package tangible;
//----------------------------------------------------------------------------------------
// Copyright © 2006 - 2015 Tangible Software Solutions Inc.
// This class can be used by anyone provided that the copyright notice remains intact.
//
// This class provides the ability to convert basic C++ 'cin' behavior.
//----------------------------------------------------------------------------------------
public final class ConsoleInput
{
private static boolean goodLastRead = false;
public static boolean lastReadWasGood()
{
return goodLastRead;
}
public static String readToWhiteSpace(boolean skipLeadingWhiteSpace)
{
String input = "";
char nextChar;
while (Character.isWhitespace(nextChar = (char)System.in.read()))
{
//accumulate leading white space if skipLeadingWhiteSpace is false:
if (!skipLeadingWhiteSpace)
{
input += nextChar;
}
}
//the first non white space character:
input += nextChar;
//accumulate characters until white space is reached:
while (!Character.isWhitespace(nextChar = (char)System.in.read()))
{
input += nextChar;
}
goodLastRead = input.length() > 0;
return input;
}
public static String scanfRead()
{
return scanfRead(null, -1);
}
public static String scanfRead(String unwantedSequence)
{
return scanfRead(unwantedSequence, -1);
}
public static String scanfRead(String unwantedSequence, int maxFieldLength)
{
String input = "";
char nextChar;
if (unwantedSequence != null)
{
nextChar = '\0';
for (int charIndex = 0; charIndex < unwantedSequence.length(); charIndex++)
{
if (Character.isWhitespace(unwantedSequence.charAt(charIndex)))
{
//ignore all subsequent white space:
while (Character.isWhitespace(nextChar = (char)System.in.read()))
{
}
}
else
{
//ensure each character matches the expected character in the sequence:
nextChar = (char)System.in.read();
if (nextChar != unwantedSequence.charAt(charIndex))
return null;
}
}
input = (new Character(nextChar)).toString();
if (maxFieldLength == 1)
return input;
}
while (!Character.isWhitespace(nextChar = (char)System.in.read()))
{
input += nextChar;
if (maxFieldLength == input.length())
return input;
}
return input;
}
}
Note the heavy use of the static keyword. That is not considered good Java. So even well-written procedural C++ converted straight into Java will not be well received. If it is an assignment, you will not get a high grade, even if it works. You are supposed to leave "the static environment of main()" as quickly as possible and never look back.
Re: Convert C++ Code to Java
It's not even a 'correct' conversion. I used unsigned to remove the need to check for a value < 0 - but Java has gone back to using int so the checks for < 0 need to be re-instated.
Re: Convert C++ Code to Java
Quote:
Originally Posted by
2kaud
It's not even a 'correct' conversion. I used unsigned to remove the need to check for a value < 0 - but Java has gone back to using int so the checks for < 0 need to be re-instated.
Oops! Well, converting between languages is a daunting task. Nevertheless, in this case, the converter should have issued a to-do warning (as I see it usually does when it omits something). Unsigned is not part of Java but is common in C++. Maybe it is better handled in the commercial version of the converter. However, I used the converter to show that a straight conversion of procedural C++ does not produce idiomatic Java. The static keyword becomes overused. And for this purpose, the converter worked.
