telosys-symbolicvar-v1.0

8/6/2019 Telosys-SymbolicVar-v1.0

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Telosys 1

Symbolic Variables

Laurent Gurin / v 1.0 / 2009 - May

Telosys framework - Symbolic variables ( Laurent Gurin ) 2

What are symbolic variables ?

The symbolic variables are a set of predefinedexpressions for accessing server information in aTelosys tag attribute

The variables are replaced by their value when theJSP is called

Syntax : @{ variable_name, default_value, format }

Examples :


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What are symbolic variables ?

The symbolic variables are completelyindependent of the standard JSP ExpressionLanguage ( "EL" ). They can be used even in oldJava servers that doesn't support EL and JSTL.

Where can they be used ? In the "v" attribute of "t:out"

In every event attributes : onclick, onblur,

In the specific following attributes :

id namevalue txt valueoff title zone checkedcl style selecteddisabled readonly


Symbolic variables : predefined values

Predefined names : "#xxx"

Session & User @{#session-id} the current session id

@{#user-login} the current user login

@{#user-language} the current user language

@{#user-role} the current user role URL & URI

@{#webapp-url} "http://localhost:8080/appli/"

@{#webapp-uri} "/appli/"

@{#screenmap-url} "http://localhost:8080/appli/screenmap"

@{#screenmap-uri} "/appli/screenmap"


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HTTP request parameters : @{#paramcount} number of parameters

@{#param-xxx} value of the "xxx" parameter

Iterations : @{#count} the current count value ( from 1 to n )

@{#count-parity} "even" or "odd"

@{#index} the current index valuefrom index-base (0 by default) to n

@{#index-parity} "even" or "odd"



Screen Context : @{#context-id} 0 to N

@{#context-name} "MYSCREEN" ( from ScreenContext registry )

Screen Map ( from "screens.xml" ) : @{#screen-name} "S002"

@{#screen-type} "html" or "xul"

@{#screen-path} "/screen/tpl/html/model1.jsp"

@{#screen-body} "S002.jsp"

@{#screen-body-path} "/screen/S002.jsp"

@{#screen-css} "S002.css"

@{#screen-css-path}

@{#screen-js} "S002.js"

@{#screen-js-path} "/screen/script/S002.js


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Symbolic variables for Java beans

Any Java bean can be accessed with the standard"dot" notation : @{agency.city} value of the attribute "city" of the bean

"agency"

@{.city} value of the attribute "city" of the "currentbean" ( the "." in first position defines an attribute )

@{agency} string value of the bean "agency"( using the "toString" method of the bean )

Example :


Symbolic variables for Java beans

Bean search order : When a bean is specified by a name

( e.g. @{agency.code} ), the name is searched in thefollowing scopes order : 1 screen-context data element ( Telosys ) (*)

2 screen-context attribute ( Telosys ) (*)

3 standard servlet request ( standard "request scope" ) 4 screen-session ( Telosys )

5 standard http session (standard "session scope" )

6 screen-application ( Telosys )

7 standard servlet context (standard "application scope" )

(*) The screen-context is defined only in screen actions, not in aservice call


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Symbolic variables and services

Special bean name : "RENDERER-BEAN" ( or "RENDERER_BEAN" )

points the "service result" object( this special name is usable only in a service renderer )

Example :

Any other bean can be used in a classical way if

the service expose it in the request scope

Agency result = new Agency();

serviceResponse.setResult(result);

Agency agency = new Agency();

serviceResponse.expose("agency", agency);


Symbolic variables for List

Size of a Collection, VOList or DataSet : @{mylist.size} list size

Example ( list with a VOList ) :

element(s) in the list :


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Symbolic variables for DataSet

DataSet cells can be accessed with a numbercorresponding to the column number of thecurrent DataRow ( 1 to n ) : @{.1} or @{1} value of the column 1

@{.2} or @{2} value of the column 2

etc

Example ( list with a Dataset ) :

Default value & format


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Symbolic variables - Default value

If the symbolic variable is not found If there is a default value : it is used

Else : a void string is returned ( "" )

The default value is located at the 2nd positionexamples : @{myint,123} "123" if not found

@{myint,123,000000} "123" if not found

@{mystr,'bla bla'} "bla bla" if not found

@{mystr,bla bla} likewise (the quotes are optional)

When the default value is used, it is returned"as is", the format is not applied on a default value


Symbolic variables - Format

The format is located at the 3d positionexamples : @{myint,,00000} "00123" for 123

@{myint,not found,000000} likewise

@{mydate,,'yyyy-MM-dd'} "2008-03-30" @{mydate,,yyyy-MM-dd} likewise

(the quotes are optional)

Without format, the "toString" method of theobject is used

The format is not applied on the default value


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Symbolic variables - Format

Boolean object format : Without format boolean returns "true" or "false"

Format syntax : "value-if-true|value-if-false"examples : @{mybool,,Yes|No}

@{mybool,,Black|White}

@{mybool,,1|0}

Number object format(Integer, Long, Double, BigDecimal, BigInteger, )

If the format contains "|"

the "java.text.ChoiceFormat" is used Else the "java.text.DecimalFormat" is used

Date object format The "java.text.SimpleDateFormat" is used

Seethe

javadoc

Use cases


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Use cases

Print a bean attributes :

Using "with/without" tag :

Bean not found

Code

Name

City


Use cases

Iterate on a list :


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Use cases

Populate combo box items from a list of beans :

Populate combo box items from a DataSet :

It's the same for list box,with tags and

THE END

telosys-symbolicvar-v1.0

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