groovycode/blog1.txt at master · javaiskool/groovycode · GitHub

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title
groovy basics for Java Programmer
====

One of the easy ways to install groovy is to use sdkman
Once installation is complete, make sure path has been set, by typing groovy -v

create a file having extension groovy as follows:

one.groovy

class Two
{
static void main(String[] args)
{
println 'hello'
println ("hi");

}
}


we can run the file as follows:

groovy one.groovy
====

the output is
hello

=======
lessons:
1. semi-colon is optional. In java semi-colon is must to terminate a statement.
2. string literal can be in single quotes as well as in double quotes. In Java String literals can only be enclosed in double quotes.
3. we did not compile the file instead just ran the source code
4 parentheses is optional when calling a method
=======


class Two
{
static void main(String[] args)
{
int num
println num
}
}

output is 0
========
lessons:
local variable is initialised with default value. In java it is an error
=========

class Two
{
static void main(String[] args)
{

int k

if(k)
println 'yes'
else
println 'no'

}
}
=========
lessons:
output is no. 0 and null are considered as false and non-zero and not null values are considered as true
=========