The java comments are statements that are not executed by the compiler and interpreter. The comments can be used to provide information or explanation about the variable, method, class or any statement. It can also be used to hide program code for specific time.
Three types of comment in Java
1. Single line comment
Syntax
// This is single line comment
// This line won't be executed
Program
publicclass SingleLineComment
{
publicstaticvoid main(String args[])
{
// break keyword example
for(int i=1; i<=10; i++)
{
if(i==6)
{
break;
}
System.out.println(i);
}
}
}
Output
1
2
3
4
5
2. Multi line comment
Syntax
/* This is multi
line commment
This line won't
be executed */
Program
publicclass MultiLineComment
{
publicstaticvoid main(String args[])
{
for(int i=1; i<=10; i++)
{
/* Exmple of
break
keyword */
if(i==6)
{
break;
}
System.out.println(i);
}
}
}
Output
1
2
3
4
5
3. Documentation comment
Syntax
/** This is
documentation
comment */
Program
publicclass DocComment
{
publicstaticvoid main(String args[])
{
}
/** The add() method returns addition of given numbers.*/
publicstaticint add(int a, int b)
{
return a+b;
}
/** The div() method returns divison of given numbers.*/
publicstaticint div(int a, int b)
{
return a/b;
}
}
Output
javac DocComment.java
javadoc DocComment.java
Explanation
The documentation comment is used to create documentation API. To create documentation API, you need to use javadoc tool.
Now, there will be HTML files created for your Calculator class in the current directory. Open the HTML files and see the explanation of Calculator class provided through documentation comment.
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