JDT stands for Java Development Tools. The JDT compiler is the Java compiler
included with the Eclipse IDE (Integrated Development Environment). The JDT
compiler is needed only when the JasperReports application is running under a Java
Runtime Environment (JRE), and not under a full JDK.
When compiling reports, JasperReports creates temporary Java files and compiles
them. When using a JDK, JasperReports takes advantage of tools.jar for this
functionality. Since a JRE does not include tools.jar , the JDT compiler is needed.
The JasperReports project ZIP file version 1.2.2 includes the JDT compiler. It can
be found under the lib subdirectory of the directory created when extracting the
project ZIP file. The file to be added to your CLASSPATH is jdt-compiler.jar .
This file cannot be downloaded separately. Therefore, if we need to execute our
code under a JRE, we need to download the JasperReports project ZIP file, since it
includes the file, which is needed for report compilation.
JasperReports requires either tools.jar or the JDT when
compiling JRXML templates into binary JasperReports
templates. A JRE is sufficient if our Java application does
not compile reports.
When using a JDBC datasource, the appropriate JDBC driver for our specific
RDBMS is needed. The following table lists popular relational database systems and
the required JAR files to be added to the CLASSPATH �exact file names may vary
depending on the version). The names shown in the table reflect the latest stable
versions at the time of writing:
Driver JAR Files