protected void checkConfiguration()

in src/main/org/apache/tools/ant/taskdefs/Java.java [143:215]
73 lines of code
28 McCabe index (conditional complexity)

    protected void checkConfiguration() throws BuildException {
        String classname = getCommandLine().getClassname();
        String module = getCommandLine().getModule();
        final String sourceFile = getCommandLine().getSourceFile();
        if (classname == null && getCommandLine().getJar() == null && module == null && sourceFile == null) {
            throw new BuildException("Classname must not be null.");
        }
        if (!fork && getCommandLine().getJar() != null) {
            throw new BuildException(
                "Cannot execute a jar in non-forked mode. Please set fork='true'. ");
        }
        if (!fork && getCommandLine().getModule() != null) {
            throw new BuildException(
                "Cannot execute a module in non-forked mode. Please set fork='true'. ");
        }
        if (!fork && sourceFile != null) {
            throw new BuildException("Cannot execute sourcefile in non-forked mode. Please set fork='true'");
        }
        if (spawn && !fork) {
            throw new BuildException(
                "Cannot spawn a java process in non-forked mode. Please set fork='true'. ");
        }
        if (getCommandLine().getClasspath() != null
            && getCommandLine().getJar() != null) {
            log("When using 'jar' attribute classpath-settings are ignored. See the manual for more information.",
                Project.MSG_VERBOSE);
        }
        if (spawn && incompatibleWithSpawn) {
            getProject().log(
                "spawn does not allow attributes related to input, output, error, result",
                Project.MSG_ERR);
            getProject().log("spawn also does not allow timeout", Project.MSG_ERR);
            getProject().log(
                "finally, spawn is not compatible with a nested I/O <redirector>",
                Project.MSG_ERR);
            throw new BuildException(
                "You have used an attribute or nested element which is not compatible with spawn");
        }
        if (getCommandLine().getAssertions() != null && !fork) {
            log("Assertion statements are currently ignored in non-forked mode");
        }
        if (fork) {
            if (perm != null) {
                log("Permissions can not be set this way in forked mode.", Project.MSG_WARN);
            }
            log(getCommandLine().describeCommand(), Project.MSG_VERBOSE);
        } else {
            if (getCommandLine().getVmCommand().size() > 1) {
                log("JVM args ignored when same JVM is used.",
                    Project.MSG_WARN);
            }
            if (dir != null) {
                log("Working directory ignored when same JVM is used.",
                    Project.MSG_WARN);
            }
            if (newEnvironment || null != env.getVariables()) {
                log("Changes to environment variables are ignored when same JVM is used.",
                    Project.MSG_WARN);
            }
            if (getCommandLine().getBootclasspath() != null) {
                log("bootclasspath ignored when same JVM is used.",
                    Project.MSG_WARN);
            }
            if (perm == null && SecurityManagerUtil.isSetSecurityManagerAllowed()) {
                perm = new Permissions(true);
                log("running " + this.getCommandLine().getClassname()
                    + " with default permissions (exit forbidden)", Project.MSG_VERBOSE);
            }
            log("Running in same VM " + getCommandLine().describeJavaCommand(),
                Project.MSG_VERBOSE);
        }
        setupRedirector();
    }