compiler.java

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     * Compile the servlet from .java file to .class file
     */
    protected abstract void generateClass(String[] smap)
        throws FileNotFoundException, JasperException, Exception;
    
    
    /** 
     * Compile the jsp file from the current engine context
     */
    public void compile()
        throws FileNotFoundException, JasperException, Exception
    {
        compile(true);
    }

    /**
     * Compile the jsp file from the current engine context.  As an side-
     * effect, tag files that are referenced by this page are also compiled.
     * @param compileClass If true, generate both .java and .class file
     *                     If false, generate only .java file
     */
    public void compile(boolean compileClass)
        throws FileNotFoundException, JasperException, Exception
    {
        compile(compileClass, false);
    }

    /**
     * Compile the jsp file from the current engine context.  As an side-
     * effect, tag files that are referenced by this page are also compiled.
     *
     * @param compileClass If true, generate both .java and .class file
     *                     If false, generate only .java file
     * @param jspcMode true if invoked from JspC, false otherwise
     */
    public void compile(boolean compileClass, boolean jspcMode)
        throws FileNotFoundException, JasperException, Exception
    {
        if (errDispatcher == null) {
            this.errDispatcher = new ErrorDispatcher(jspcMode);
        }

        try {
            String[] smap = generateJava();
            if (compileClass) {
                generateClass(smap);
            }
        } finally {
            if (tfp != null) {
                tfp.removeProtoTypeFiles(null);
            }
            // Make sure these object which are only used during the
            // generation and compilation of the JSP page get
            // dereferenced so that they can be GC'd and reduce the
            // memory footprint.
            tfp = null;
            errDispatcher = null;
            pageInfo = null;

            // Only get rid of the pageNodes if in production.
            // In development mode, they are used for detailed
            // error messages.
            // http://issues.apache.org/bugzilla/show_bug.cgi?id=37062
            if(!this.options.getDevelopment()) {
                pageNodes = null;
            }

            if (ctxt.getWriter() != null) {
                ctxt.getWriter().close();
                ctxt.setWriter(null);
            }
        }
    }

    /**
     * This is a protected method intended to be overridden by 
     * subclasses of Compiler. This is used by the compile method
     * to do all the compilation. 
     */
    public boolean isOutDated() {
        return isOutDated( true );
    }

    /**
     * Determine if a compilation is necessary by checking the time stamp
     * of the JSP page with that of the corresponding .class or .java file.
     * If the page has dependencies, the check is also extended to its
     * dependeants, and so on.
     * This method can by overidden by a subclasses of Compiler.
     * @param checkClass If true, check against .class file,
     *                   if false, check against .java file.
     */
    public boolean isOutDated(boolean checkClass) {

        String jsp = ctxt.getJspFile();

        if (jsw != null
                && (ctxt.getOptions().getModificationTestInterval() > 0)) {
 
            if (jsw.getLastModificationTest()
                    + (ctxt.getOptions().getModificationTestInterval() * 1000) 
                    > System.currentTimeMillis()) {
                return false;
            } else {
                jsw.setLastModificationTest(System.currentTimeMillis());
            }
        }
        
        long jspRealLastModified = 0;
        try {
            URL jspUrl = ctxt.getResource(jsp);
            if (jspUrl == null) {
                ctxt.incrementRemoved();
                return false;
            }
            URLConnection uc = jspUrl.openConnection();
            jspRealLastModified = uc.getLastModified();
            uc.getInputStream().close();
        } catch (Exception e) {
            e.printStackTrace();
            return true;
        }

        long targetLastModified = 0;
        File targetFile;
        
        if( checkClass ) {
            targetFile = new File(ctxt.getClassFileName());
        } else {
            targetFile = new File(ctxt.getServletJavaFileName());
        }
        
        if (!targetFile.exists()) {
            return true;
        }

        targetLastModified = targetFile.lastModified();
        if (checkClass && jsw != null) {
            jsw.setServletClassLastModifiedTime(targetLastModified);
        }   
        if (targetLastModified < jspRealLastModified) {
            if( log.isDebugEnabled() ) {
                log.debug("Compiler: outdated: " + targetFile + " " +
                    targetLastModified );
            }
            return true;
        }

        // determine if source dependent files (e.g. includes using include
        // directives) have been changed.
        if( jsw==null ) {
            return false;
        }
        
        List depends = jsw.getDependants();
        if (depends == null) {
            return false;
        }

        Iterator it = depends.iterator();
        while (it.hasNext()) {
            String include = (String)it.next();
            try {
                URL includeUrl = ctxt.getResource(include);
                if (includeUrl == null) {
                    return true;
                }

                URLConnection includeUconn = includeUrl.openConnection();
                long includeLastModified = includeUconn.getLastModified();
                includeUconn.getInputStream().close();

                if (includeLastModified > targetLastModified) {
                    return true;
                }
            } catch (Exception e) {
                e.printStackTrace();
                return true;
            }
        }

        return false;

    }

    
    /**
     * Gets the error dispatcher.
     */
    public ErrorDispatcher getErrorDispatcher() {
	return errDispatcher;
    }


    /**
     * Gets the info about the page under compilation
     */
    public PageInfo getPageInfo() {
	return pageInfo;
    }


    public JspCompilationContext getCompilationContext() {
	return ctxt;
    }


    /**
     * Remove generated files
     */
    public void removeGeneratedFiles() {
        try {
            String classFileName = ctxt.getClassFileName();
            if (classFileName != null) {
                File classFile = new File(classFileName);
                if( log.isDebugEnabled() )
                    log.debug( "Deleting " + classFile );
                classFile.delete();
            }
        } catch (Exception e) {
            // Remove as much as possible, ignore possible exceptions
        }
        try {
            String javaFileName = ctxt.getServletJavaFileName();
            if (javaFileName != null) {
                File javaFile = new File(javaFileName);
                if( log.isDebugEnabled() )
                    log.debug( "Deleting " + javaFile );
                javaFile.delete();
            }
        } catch (Exception e) {
            // Remove as much as possible, ignore possible exceptions
        }
    }

    public void removeGeneratedClassFiles() {
        try {
            String classFileName = ctxt.getClassFileName();
            if (classFileName != null) {
                File classFile = new File(classFileName);
                if( log.isDebugEnabled() )
                    log.debug( "Deleting " + classFile );
                classFile.delete();
            }
        } catch (Exception e) {
            // Remove as much as possible, ignore possible exceptions
        }
    }
}