Question

1.In C++, C#, Java. Discuss string operations functions, with examples. Then make Comparison of programming languages  

2.String and StringBuffer (C#, Java) with examples.

Answer 1

In C++, string is an object of std::string class that represents sequence of characters. We can perform many operations on strings such as concatenation, comparison, conversion etc.

int compare(const string& str)	It is used to compare two string objects.
int length()	It is used to find the length of the string.
void swap(string& str)	It is used to swap the values of two string objects.
string substr(int pos,int n)	It creates a new string object of n characters.

In C# programming, string is another kind of data type that represents Unicode Characters. It is the alias of System.String, however, you can also write System.String instead of a string. It is the sequence of character in which each character is a Unicode character.

String Functions	Definitions
Clone()	Make clone of string.
CompareTo()	Compare two strings and returns integer value as output. It returns 0 for true and 1 for false.
Contains()	The C# Contains method checks whether specified character or string is exists or not in the string value.
EndsWith()	This EndsWith Method checks whether specified character is the last character of string or not.

In Java, a string is a sequence of characters. For example, "hello" is a string containing a sequence of characters 'h', 'e', 'l', 'l', and 'o'.Unlike other programming languages, strings in Java are not primitive types (like int, char, etc). Instead, all strings are objects of a predefined class named String

Methods	Description
concat()	joins the two strings together
equals()	compares the value of two strings
charAt()	returns the character present in the specified location
getBytes()	converts the string to an array of bytes
indexOf()	returns the position of the specified character in the string

C#	C++
Comparably slower.	Comparably faster.
Mainly built for Windows platform.	Compatible with multiple platforms including Windows, Linux and Mac.
Used for Web or Desktop application.	Mainly used for Performance-oriented application with hardware interaction.
Has inbuilt garbage collector.	No support for garbage collection.
Compiler warnings are displayed at the time of writing the code.	Need to write and compile the entire code to check for error.

C#	Java
C# runs on CLR.	Java runs on JVM.
C# needs .Net framework to run.	JDK is required for Java.
C# can be used to develop both Web, and Game development along with Mobile development.	Java is mainly used for designing complex web applications.
Not as efficient as Java.	Very efficient, flexible and cross platform compatible.
Offers single type of exception.	Offers both check and uncheck exceptions.
Libraries development and update depends upon Microsoft.	Open source nature allows continuous development and update.
Decent server side performance.	Useful for server side interaction.

Parameter of Comparison	C++	Java
Based on the concept of	Write once compile anywhere	Write once run anywhere everywhere
Type of Programming Language	Procedural and object-oriented language	Only object-oriented language
Type of Language	Compiled	Compiled + Interpreted
Dependency on platform	Platform dependent language	Not dependent on platform
Other languages compatibility	Yes, with most high-level languages	Not compatible, no backward compatibility
Mechanism of Input	Input/output statements	More complex
Relationship of source code and filename	No relationship	Yes, relationship exists
Interface with libraries	Allows direct calls to native system libraries	Only through Java native interface
Portability	Not portable	Portability is there as it can be executed on any platform
Is operator overloading allowed?	Yes	No, only method overloading allowed
Type of root hierarchy	No root hierarchy	Follows single root hierarchy
Access control	Flexible	Complex
Detection of runtime error responsibility	Responsibility of programmer	System controlled
Management of Memory	Manual	System-managed

2)In c#

No	String	StringBuffer
1	String class is immutable	StringBuffer class is mutable (modifiable)
2	Consumes more memory during concatenation	Consumes less memory during concatenation
3	Slow performance	Fast performance
4	Overrides equals() and hashcode() methods of the object class	Doesn't override the equals() and hashcode() methods of the object class

In java

No.	String	StringBuffer
1)	String class is immutable.	StringBuffer class is mutable.
2)	String is slow and consumes more memory when you concat too many strings because every time it creates new instance.	StringBuffer is fast and consumes less memory when you cancat strings.
3)	String class overrides the equals() method of Object class. So you can compare the contents of two strings by equals() method.	StringBuffer class doesn't override the equals() method of Object class.

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