hmi.util
Class Resources

java.lang.Object
  hmi.util.Resources

public class Resources
extends Object

Resources are objects that serve as an ``anchor'' for loading files called ``resources''. Such files are assumed to be at a fixed place within the directory structure associated with a project, so no interactive file dialog is needed. They are, however, not assumed to be at a fixed place within the file system of the OS, so as to avoid undesirable system dependencies. Think of a situation where an application is packaged in the form of a single executable jar file, that has to run from within some unknown directory on an unknown machine. In this case, about the only location that we can rely on is the jar archive itself, so resource files should be specified relative to the jar archive. A Resources object determines a data directory inside such a jar archive, and will open files inside this directory, via the getReader() or getFileStream method. By convention the name of this data directory follows the package structure, so for example, the data used by some class inside the project.vmr package shouold read data from files inside the project/vmr data directory. When the application is not run from a jar archive, the same data directory should be available, and should be included in the java run time classpath. By convention, we use a "data" or "resources" directory inside java projects, which is included in the the java classpath, either inside the Java development tool or inside the ant build scripts.

Author:

Job Zwiers

Field Summary

private static ClassLoader	loader
private static Logger	logger
private boolean	logging
private String	resourceDir
private String	resourceRoot

Constructor Summary

private	Resources()
	Resources(String resourceDir) Create a new Resources object, for a specified resource directory.

Method Summary

private static String	adjustPath2(String rootPath)
BufferedInputStream	getInputStream(String fileName) Like getReader(filename), but returns a buffered InputStream, rather than a buffered Reader.
BufferedReader	getReader(String fileName) Opens a file, and returns a buffered Reader for that file.
String	getResourceDirectory() returns the resource directory for this Resources object
String	getResourceRoot() returns the resource root directory for this Resources object
private InputStream	getUnbufferedInputStream(String fileName)
String	read(String fileName) Tries to read the specified file, and returns the contents as a String.
void	setLogging(boolean logging) Turns logging on or off

Methods inherited from class java.lang.Object

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

Field Detail

resourceRoot

private String resourceRoot

loader

private static ClassLoader loader

logger

private static Logger logger

logging

private boolean logging

resourceDir

private String resourceDir

Constructor Detail

Resources

private Resources()

Resources

public Resources(String resourceDir)

Create a new Resources object, for a specified resource directory. This directory is searched for on the run time classpath.

Method Detail

getResourceDirectory

public String getResourceDirectory()

returns the resource directory for this Resources object

getInputStream

public BufferedInputStream getInputStream(String fileName)

Like getReader(filename), but returns a buffered InputStream, rather than a buffered Reader. Returns null when the resource file could not be found.

getUnbufferedInputStream

private InputStream getUnbufferedInputStream(String fileName)

getReader

public BufferedReader getReader(String fileName)

Opens a file, and returns a buffered Reader for that file. The file is searched for in the resource directory determined by this Resources object. Assume that this method is called for a class with name C that extends "Resources". Call the package prefix for this C class "package". If "filename" is a relative path, i.e. if it does not start with a "/", then the package prefix is prepended, and the resulting file is searched for on the classpath. For the HMI projects, we assume that the data directory is included in the classpath. If "filename" is an absolute file name", than the package prefix is ignored, and the file is searched for on the class path. Returns null when the resource file could not be found.

read

public String read(String fileName)
            throws IOException

Tries to read the specified file, and returns the contents as a String. If the file cannot be opened, a null result is returned.

Throws:

IOException

setLogging

public void setLogging(boolean logging)

Turns logging on or off

adjustPath2

private static String adjustPath2(String rootPath)

getResourceRoot

public String getResourceRoot()

returns the resource root directory for this Resources object