Do you remember the time in your schools when you read about part of speech, verbs and adjectives?
These are considered as the building blocks to learn the English language. There will be no basic structure without them.
Similarly, token serves the basic structure in the programming languages. And, java is no exception to this rule.
Tokens are regarded as the foundation of a code script. When you start encountering terms like keywords, operators, tokenization, you realise you are studying java tokens.
Though all these tokens serve versatile purposes, they have certain disadvantages or limitations that every programmer should know.
So stay till the end of this blog as we are going to cover the knits and grits related to this vital topic.
Let’s get started!
Tokens – basics
Tokens are regarded as the building blocks of codes which include operators, keywords or other syntactic stuff that are related to a particular language. Java compiler works in the way to identify these tokens that is based on delimiters to convert it into bytecode.
As most languages contain spaces or tabs, a carriage will return characters as the delimiters. Though, they are not part of tokens but help to identify them.
Tokens in Java
The concept of tokens is basically considered as part of the central functioning of the java language. It mainly comprises of classes and methods that involves some of the most useful functions for the programmers to know.
Java tokens is the concept that acts as a central function of java. Tokens are considered as the smallest unit in the java language. A compiler will break down lines of codes as the tokens. Then they will be separated by the delimiters. So, it would be helpful for the compiler to detect all types of errors.
Types of Tokens In Java
When you are studying java language, you should know about several types of token which includes the following:
Keywords
Keywords in the java language are reserved words with special meaning. Each of them is assigned a specific task that cannot be changed by any user.
It should be written in lowercase because java is the case sensitive language. Some of the most widely used keywords in the Java language are abstract, byte, boolean, new, float, catch, else, char, byte, break, continue and many more.
Though, some of the limitations of keywords are:
- Sometimes it can be difficult to implement
- Keywords can only be written in lowercase
- They are not allowed to being used as variables and object
Identifiers
Any method name, variable name, class name is called the identifier in java language. The user normally defines these identifiers. When you assign an identifier to the java program, you can refer to the value that is being associated with the statement.
Features of identifiers are:
- They always begins with the letter or an underscore
- They can have combination of characters
- They are case sensitive
- Identifier will have any length
- Their names cannot contain any kind of white spaces
Limitations of identifier are:
- Sometimes it can be difficult to find an identifier
- You can’t use keywords as the identifiers
- You can’t use digits at the start of identifiers
Literals
The literals in java language are mainly similar to the normal variables. Once their values are assigned, they can’t be changed. These literals can basically belong to any type of language.
Literals can generally take the form of an integer, a boolean and a string literal. The user can express it with the help of some defined constants.
The syntax that can be used in the case of literals is:
Final data_type variable_name
The main kinds of literals which are used in the Java language are int, boolean, double, float, char and string.
Limitations of literals are:
- Once the value is assigned, you can’t change it
- It can be sometimes difficult to implement in the program
Operators
Operators are known to perform different operations on various entities. When any compiler sees the operator, it helps in tokenizing it to perform any further operations. Moreover, you can use certain other operators to perform different types of functionalities.
Some of the common operators are;
- Arithmetic operators: +, – , %
- Assignment operators: = + = – =
- Logical operators: &&
- Ternary operators: stat 1 : stat 2
- Shift operator: >>, <<
Limitations of operators are:
- Once you add an operator, you can’t change it
- Sometimes it can be difficult to understand operators
Separators
These are touted as specific symbols which are also called punctuators. They have some special meaning. Hence, they can’t be used anywhere else.
- Brackets []: They are defined as arrays that represent single or multiple scripts
- Braces {} : They have the start and end-line blocks
- Comma [,] It separates two or more statements
- Semicolon [:] : This invokes your initialization list
Tokenization in Java
Tokenization is regarded as the process where you will extract all tokens from the source code. It has built-in-classes called stringtokenizer which break the tokens into the form of strings.
Features of tokenization in java are:
- It doesn’t make a distinction between the identifiers or numbers
- It doesn’t identify any skip comments
- It maintain its current position with the help of strings
- Object token can be returned with the usage of a substring
Limitations of tokenization in java are:
- They sometimes fail to serve your input data
- They may not securely manage your overall data in an ideal way
- Sometimes it is difficult to implement the concepts
Additional Learning: finalize method in java
When you are learning java concepts, you can’t leave the topic of finalize method in java. This method states that in the object class, the given garbage collector would always be called out for destroying the object in order to perform the needed clean up duty. Once the method is complete, the object will be destroyed.
Wrapping Up
Java tokens are an essential java concept that every programmer should know. Learn about types of tokens in java with this blog post and learn about their functions and applications to strengthen your knowledge base.
All the best!
