org.eclipse.mtj.core.model.preverifier
Class StandardPreverifierFactory

java.lang.Object
  org.eclipse.mtj.core.model.preverifier.StandardPreverifierFactory

public class StandardPreverifierFactory
extends Object

A factory implementation for generating instances of StandardPreverifier with the appropriate parameters. Those parameters are retrieved by running the preverifier and using the output to make an educated guess concerning the required parameter structure.

There are three main categories of preverifiers that are supported by this class, all of which are presumably derived from (or are copies of) Sun preverifiers:

• The most basic preverifier takes no command line arguments to "tune" its performance. An example is the preverifier that comes with the Motorola SDK 4.1, Emulator 7.2. Its "usage" goes something like this:
  

    Usage: preverify [options] classnames|dirnames ...
   
    where options include:
    -classpath <directories separated by ';'>
    Directories in which to look for classes
    -d <directory> Directory in which output is written (default is ./output/)
    @<filename>    Read command line arguments from a text file
   

  With this category, we do not differentiate between CLDC 1.0 and CLDC 1.1 preverification.

• The second, more recent category of preverifier has command line arguments that allow the user to affect exactly what checks are performed during preverification. Usage for this category looks like this:

    Usage: preverify [options] classnames|dirnames ...
   
    where options include:
    -classpath     <directories separated by ';'>
    Directories in which to look for classes
    -d <directory> Directory in which output is written (default is ./output/)
    -cldc          Checks for existence of language features prohibited
    by CLDC (native methods, floating point and finalizers)
    -nofinalize    No finalizers allowed
    -nonative      No native methods allowed
    -nofp          No floating point operations allowed
    @<filename>    Read command line arguments from a text file
    Command line arguments must all be on a single line
    Directory names must be enclosed in double quotes (")
   

  Some preverifiers in this category support a -cldc1.0 argument instead of, or in addition to the -cldc argument.

  CLDC 1.0 preverification should prevent the use of floating point ( -nofp) native methods (-nonative) and finalizers ( -nofinalize), all of which is accomplished by the use of the -cldc (or -cldc1.0) parameter. For CLDC 1.1, however, floating point is allowed, although finalizers and native methods are still prohibited.

  For this category of preverifiers, we use the options -nofp -nonative -nofinalize for CLDC 1.0 preverification and -nonative -nofinalize for CLDC 1.1 preverification. We don't attempt to use the -cldc or -cldc1.0 argument for CLDC 1.0 because it's simpler and more bullet-proof just to use the individual arguments.

• The third category of preverifiers represent a yet more modern evolution. These add a -target option that effectively selects between two different preverifiers. Usage typically looks like this:

    Usage: preverify [options] classnames|dirnames ...
   
    where options include:
    -classpath     <directories separated by ';'>
    Directories in which to look for classes
    -d <directory> Directory in which output is written (default is ./output/)
    [ -cldc1.0 | -cldc ]
    Checks for existence of language features prohibited
    by CLDC 1.0 (native methods, floating point and finalizers)
    -target <CLDC1.1 | CLDC1.0>
    Which preverifier to run
    -nofinalize    No finalizers allowed
    -nonative      No native methods allowed
    -nofp          No floating point operations allowed
    @<filename>    Read command line arguments from a text file
    Command line arguments must all be on a single line
    Directory names must be enclosed in double quotes (")
   

  Thus, this category of preverifier is essentially identical to the second set, but with the addition of the -target option. Oddly enough, experience shows that specifying CLDC 1.1 or CLDC 1.0 using the -target option does not result in automatic selection of the appropriate -nofp, -nonative, and/or -nofinalize options. Thus, we include these in addition to the -target option.

  As a result, for this category of preverifiers, we use the options -target CLDC1.0 -nofp -nonative -nofinalize for CLDC 1.0 preverification and -target CLDC1.0 -nonative -nofinalize for CLDC 1.1

The basic strategy of this class is to run the preverifier without any command line arguments and capture the result. We then inspect the output for the presence of the various options and, when we find them, add them to the arguments we will use for the various preverifications. Note that we have to check both the stdout results and the stderr results, because some preverifiers send their usage to stdout (Sun) and other send it to stderr (Motorola).

Method Summary

static StandardPreverifier

createPreverifier(File preverifierExecutable) Create a new StandardPreverifier instance for the specified executable.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

createPreverifier

public static StandardPreverifier createPreverifier(File preverifierExecutable)
                                             throws CoreException

Create a new StandardPreverifier instance for the specified executable. Returns null if the preverifier cannot be created for some reason.

Parameters:

preverifierExecutable -

Returns:

Throws:

CoreException - if failed to get the preverifier parameters.