Features removed in java:
- Java doesn’t support doesn’t pointers to avoid unauthorized access to memory locations.
- Java does not include structures, unions, and enum data types.
- Java does not support operator overloading.
- Preprocessor plays a less important role in C++ and so eliminated entirely in java.
- Java does not perform automatic type conversions that result in a loss of precision.
New features added in Java:
- Multithreading, allows two or more pieces of the same program to execute concurrently.
- C++ has a set of library functions that use a common header file. But java replaces it with its own set of API classes.
- It adds packages and interfaces.
- Java supports automatic garbage collection.
- break and continue statements have been enhanced in java to accept labels as targets.
- The use of Unicode characters ensures portability.
- Java does not support global variables. Every method and variable is declared within a class and forms part of that class.
- Java does not allow default arguments.
- Java does not support the inheritance of multiple superclasses by a subclass (i.e., multiple inheritances). This is accomplished by using the ‘interface’ concept.
- It is not possible to declare unsigned integers in java.
- In Java, objects are passed by reference only. In C++ objects may be passed by value or reference.
Features that differ:
- Though C++ and java support Boolean data type, C++ takes any nonzero value as true and zero as false. True and false in java are predefined literals that are valued for a Boolean expression.
- Java has replaced the destructor function with a finalize) function.
- C++ supports exception handling that is similar to javas. However, in C+ there is no requirement that a thrown exception be caught.
C++ vs Java:
| ComparisonIndex | C++ | Java |
| Platform- independent | C++ is platform-dependent. | Java is platform-independent. |
| Mainly used for | C++ is mainly used for system programming. | Java is mainly used for application programming. It is widely used in Windows, web-based, enterprise, and mobile applications. |
| Goto | C++ supports the goto statement. | Java doesn’t support the goto statement. |
| Compiler and Interpreter | C++ uses compilers only. | Java uses a compiler and interpreter both. |
| Call by Value and Call by reference | C++ supports both call-by-value and call-by-reference. | Java supports call-by-value only. There is no call by reference in java. |
| Structure and Union | C++ support structures and unions. | Java doesn’t support structures and unions. |
| Thread support | C++ doesn’t have built-in support for threads. | Java has built-in thread support. |
| Documentation comment | C++ doesn’t support documentation comments. | Java supports documentation comment (/**. . */) to create documentation for java source code. |
| unsigned right shift >>> | C++ doesn’t support >>> operator | Java supports unsigned right shift >>> operator |
