Response interface 



public abstract interface Response

Interface to response generated from a custom tag. This interface includes methods for writing output, generating queries, and setting variables in the calling page.

    Methods

    Returns

    Syntax

    Description

    Query

    addQuery(String name, String[] columns)

    Adds a query to the calling template.

    void

    setVariable(String name, String value)

    Sets a variable in the calling template.

    void

    write(String output)

    Outputs text back to the user.

    void

    writeDebug(String output)

    Writes text output into the debug stream.

    addQuery

    Description

    Adds a query to the calling template. The query can be accessed by CFML tags in the template. After calling addQuery, the query is empty (it has 0 rows). To populate the query with data, call the Query methods addRow and setData.

    Returns the Query that was added to the template.

    Category

    Response interface

    Syntax

    public Query addQuery(String name, String[] columns)

    Throws

    IllegalArgumentException
    If the name parameter is not a valid CFML variable name.

    See also

    addRow, setData

    Parameters

    Parameter

    Description

    name

    The name of the query to add to the template

    columns

    The column names to use in the query

    Example

    The following example adds a query named People to the calling template. The query has two columns (FirstName and LastName) and two rows:

    // Create string array with column names (also track columns indexes) 
String[] columns = { "FirstName", "LastName" } ; 
int iFirstName = 1, iLastName = 2 ; 
 
// Create a query which contains these columns 
Query query = response.addQuery( "People", columns ) ; 
 
// Add data to the query 
int iRow = query.addRow() ; 
query.setData( iRow, iFirstName, "John" ) ; 
query.setData( iRow, iLastName, "Smith" ) ; 
iRow = query.addRow() ; 
query.setData( iRow, iFirstName, "Jane" ) ; 
query.setData( iRow, iLastName, "Doe" ) ;

    setVariable

    Description

    Sets a variable in the calling template. If the variable name specified exists in the template, its value is replaced. If it does not exist, a new variable is created.

    Category

    Response interface

    Syntax

    public void setVariable(String name, String value)

    Throws

    IllegalArgumentException
    If the name parameter is not a valid CFML variable name.

    Parameters

    Parameter

    Description

    name

    The name of the variable to set

    value

    The value to set the variable to

    Example

    For example, this code sets the value of a variable named MessageSent based on the success of an operation performed by the custom tag: 

    boolean bMessageSent ; 
 
    ...attempt to send the message... 
 
    if ( bMessageSent == true ) 
    { 
        response.setVariable( "MessageSent", "Yes" ) ; 
    } 
    else 
    { 
        response.setVariable( "MessageSent", "No" ) ; 
    }

    write

    Description

    Outputs text back to the user.

    Category

    Response interface

    Syntax

    public void write(String output)

    Parameters

    Parameter

    Description

    output

    Text to output

    Example

    The following example outputs the value of the DESTINATION attribute: 

    response.write( "DESTINATION = " +  
    request.getAttribute("DESTINATION") ) ;

    writeDebug

    Description

    Writes text output into the debug stream. This text is displayed to the end-user only if the tag contains the debug attribute (check for this attribute using the Request.debug method).

    Category

    Response interface

    Syntax

    public void writeDebug(String output)

    See also

    debug

    Parameters

    Parameter

    Description

    output

    The text to output

    Example

    The following example checks whether the debug attribute is present; if so, it writes a brief debug message: 

    if ( request.debug() ) 
{ 
    response.writeDebug( "debug info" ) ; 
}