Groovy Tips

Here are some productivity tips for Groovy development. Provided you have GROOVY_HOME/bin added to your path you can execute following commands:

• running Groovy shell

groovish

Type 'help' or '\h' for help.

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groovy:000>

you can e.g. type: 

   

Sting.methods.each{println it.name }

• running graphic console

groovyConsole

• running uncompiled Grovy on web server

1. Add groovy.jar from $GROOVY_HOME/embedded to server classpath (WEB-INF/lib)

2. Add groovy.servlet.GroovyServlet to WEB-INF/web.xml.
3. Place your Groovy scripts wherever you'd normally place your JSP files.
4. Create hyperlinks to your Groovy scripts

• automatic imports

Groovy automatically imports:import packages:

java.lang.*

java.util.*

java.net.*

java.io.*

java.math.BigInteger

java.math.BigDecimal

groovy.lang.*

groovy.util.*

• method pointers

In Groovy you can do the following:

def shoppingList = []

def add = shoppingList.&add

def remove = shoppingList.&remove

add "Milk"

add "Bread"

add "Beer"

remove "Beer"

add "Apple Juice"

print shoppingList

• operators

The following are operators and corresponding methods:

Operator	Method
a == b    or a != b	a.equals(b)
a+b	a.plus(b)
a-b	a.minus(b)
a*b	a.multiply(b)
a/b	a.div(b)
a%b	a.mod(b)
a++    or ++a	a.next()
a--    or --a	a.previous()
a&b	a.and(b)
a|b	a.or(b)
a[b]	a.getAt(b)
a[b] = c	a.putAt(b,c)
a << b	a.leftShift(b)
a >> b	a.rightShift(b)
a < b    or a > b    or a <= b    or a >= b	a.compareTo(b)