When you run schema compilation through the JavaTest Agent, your schema compiler will be executed in the Agent's JVM. Your implementation should provide a custom class, which implements the following interface:

package com.sun.jck.lib;

public interface SchemaCompilerTool {

    /**
    * @param xsdFiles  array of strings containing schema files
    * @param packageName  the target package
    * @param outDir  output directory where java file(s) will be generated
    * @param out  output stream for logging
    * @param err  error stream for logging
    * @return 0 if java file(s) generated successfully
    */

    int compile(String[] xsdFiles, String packageName, File outDir, PrintStream out, PrintStream err);
}

Schema compilation should be accomplished during invocation of compile method.

The JCK devtools test suite includes the following class that is fully compatible with Oracle's reference implementation and that can be used for schema compilation: com.sun.jck.lib.SchemaCompiler. The realization of the method

compile(String[] xsdFiles, String packageName, File outDir, PrintStream out, PrintStream err)
compiles a schema(s) into java source(s).

If your implementation doesn't provide such a class, please, create it and specify it here.