HowTo: java objects as data source ?

[2001 JI Open Discussion]

By: Ingo Vogt - ingov

HowTo: java objects as data source ?

2002-04-22 11:02

Hi all,

 

i try to fill my reports with data/values retrieved from pure java objects. has anyone an idea or a reference (e. g. doc, source code example) how to implement the JRDataSource interface and write the ReportLayout.xml so that the report can be filled with data from java objects ?

 

Thanks for all your helps

-Ingo

 

 

 

 

By: Artur Biesiadowski - abies

RE: HowTo: java objects as data source ?

2002-04-22 11:44

As for the report xml, you do no change anything. On java side, do something like below and pass this object as JRDataSource to one of JasperManager methods.

 

private double[][] dataFront;

private double[][] dataRear;

private int count;

private int index;

 

 

public Object getFieldValue(JRField arg0) throws JRException

{

String name = arg0.getName();

 

if ( "TubeNumber".equals(name) )

{

return new Integer((int)dataFront[0][index]);

}

else if ( "CropFront".equals(name) )

{

return new Double(dataFront[1][index]);

}

else if ( "CropRear".equals(name) )

{

return new Double(dataRear[1][index]);

}

else

{

System.out.println("Unknown field " + arg0.getName());

}

return null;

}

 

 

public boolean isFirst() throws JRException

{

return index == 0;

}

 

 

public boolean isLast() throws JRException

{

return index == count-1;

}

 

 

public boolean next() throws JRException

{

index++;

if ( index >= count )

return false;

return true;

}