The document provides an overview of Velocity usage and tips for common problems, covering variables, properties, methods, control statements, lists, maps, and comments. Additionally, it highlights the integration of Velocity with dotCMS, showcasing various view tools and their capabilities. Examples illustrate functionality such as dynamic banners, category management, and content retrieval.

1. Velocity
Tips
and
Tricks
Simple
Solu5ons
to
Common
Problems
Wed.,
April
14,
2010

2. Velocity
ABC
• Variables:
– #set($thumbWidth
=
55)
– #set($varString
=
‘ The
width
is‘)
– #set($varString
=
“${varString}
${thumbWidth}
px“)
• Proper5es:
– $news.shortSummary
– $news.expireDate
• Methods:
– #set($_today
=
$date.getDate())
– #set($_todayFormated
=
$date.format('yyyyMMddHHmmss',
$_today))

3. Velocity
ABC
• If
/
ElseIf
/
Else
statements
#if($condi5on_1)
Condi5on
1
was
met
#elseif($condi5on_2)
Condi5on
2
was
met
#else
Another
condi5on
was
met
#end
• AND
/
OR
#if($condi5on_1
&&
$condi5on_2)
…
#end
#if($condi5on_1
||
$condi5on_2)
…
#end

4. Velocity
ABC
• Lists
#set($mylist
=
[])
$mylist.add("asd")
$mylist.add(123)
$mylist.get(0)
• Maps
#set($contentList
=
$!{contents.getEmptyList()})
#set($item
=
$!{contents.getEmptyMap()})
#set($_dummy
=
$item.put('guid',
$!content.get('iden5fier')))
#set($_dummy
=
$item.put('5tle',
$content.get($5tleField)))
#set($_dummy
=
$!contentList.add($item))

5. Velocity
ABC
• Lists
and
Foreach
#foreach($item
in
$myList)
$item.5tle
<br/>
#end
• Velocity
Comments
##
Commen5ng
one
line
#*
Commen5ng
Mul5ple
lines
*#

6. Velocity
and
dotCMS
• Useful
variables:
– $EDIT_MODE
– $CONTAINER_NUM_CONTENTLETS
– $VTLSERVLET_URI

7. Velocity
and
dotCMS
• View
Tools
are
configured
in:
– dotCMSWEB-­‐INFtoolbox.xml
• Three
types
of
view
tools:
– Velocity
view
tools:
org.apache.velocity.tools….
– dotCMS
view
tools:
com.dotmarke5ng.viewtools….
– Customized
view
tools:
plugins

8. Velocity
and
dotCMS
• Velocity
View
Tool
samples:
– MathTool
– ListTool
– DateTool
hpp://velocity.apache.org/tools/devel/javadoc/

9. Velocity
and
dotCMS
• dotCMS
View
Tool
samples:
– CategoriesWebAPI
– WebAPI
– ContentsWebAPI
hpp://www.dotcms.org/api/

10. Velocity
and
dotCMS
• org.apache.velocity.tools.generic.MathTool:
– java.lang.Number
add(java.lang.Object
num1,
java.lang.Object
num2)
– java.lang.Number
div(java.lang.Object
num1,
java.lang.Object
num2)
– java.lang.Double
getRandom()
– java.lang.Number
max(java.lang.Object
num1,
java.lang.Object
num2)
– java.lang.Number
sub(java.lang.Object
num1,
java.lang.Object
num2)

11. Velocity
and
dotCMS
• org.apache.velocity.tools.generic.ListTool:
– java.lang.Boolean
contains(java.lang.Object
list,
java.lang.Object
element)
– java.lang.Object
get(java.lang.Object
list,
int
index)
– java.lang.Boolean
isEmpty(java.lang.Object
list)
– java.lang.Integer
size(java.lang.Object
list)

12. Velocity
and
dotCMS
• org.apache.velocity.tools.generic.DateTool:
– java.u5l.Date
getDate()
– java.lang.Integer
getDay(java.lang.Object
date)
– java.lang.Integer
getMonth(java.lang.Object
date)
– sta5c
java.u5l.Date
getSystemDate()
– java.lang.Integer
getYear(java.lang.Object
date)
– java.u5l.Date
toDate(java.lang.Object
obj)
– java.lang.String
toString()

13. Velocity
and
dotCMS
• CategoriesWebAPI:
– List<Category>
getChildrenCategoriesByKey(String
key)
– Category
getCategoryByKey(String
key)
– Category
getCategoryByName(String
name)
– List<Category>
getChildrenCategories(Category
cat)
– List<Category>
getChildrenCategories(Inode
inode)
– List<Category>
getChildrenCategories(String
inode)
– String
getCategoryKeyByContentlet(String
contentletInode)

14. Velocity
and
dotCMS
• WebAPI:
– int
parseInt(String
num)
– int
parseInt(int
num)
– String
toString(long
num)
– boolean
isSet(String
input)
– List<String>
splitString(String
str,
String
sep)
– String
encodeURL(String
url)
– List<Contentlet>
getContentletsByCategory(String
catInode)
–
String
getContentIden5fier(String
parsePath)
– String
getUserFullName()

15. Velocity
and
dotCMS
• ContentsWebAPI:
– Contentlet
getContentByInode(String
inode)
– Structure
getStructureByType(String
structureType)
– Structure
getStructureByInode(String
structureInode)
– Field
getFieldByName(Structure
st,
String
fieldName)
– List<Contentlet>
getContents(String
structureType,
String
categoryName)
– List<Category>
getContentletCategories(String
inode)
– List
getEmptyList()

16. Examples
• Dynamic
Banner
• Category
Example
• News
Pull
• Simple
Year
Archive