ij.io.PluginClassLoader Maven / Gradle / Ivy
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package ij.io;
import ij.IJ;
import java.io.*;
import java.net.*;
/** ImageJ uses this class loader to load plugins and resources from the
* plugins directory and immediate subdirectories. This class loader will
* also load classes and resources from JAR files.
*
* The class loader searches for classes and resources in the following order:
*
* - Plugins directory
* - Subdirectories of the Plugins directory
* - JAR and ZIP files in the plugins directory and subdirectories
*
* The class loader does not recurse into subdirectories beyond the first level.
*/
public class PluginClassLoader extends URLClassLoader {
protected String path;
/**
* Creates a new PluginClassLoader that searches in the directory path
* passed as a parameter. The constructor automatically finds all JAR and ZIP
* files in the path and first level of subdirectories. The JAR and ZIP files
* are stored in a Vector for future searches.
* @param path the path to the plugins directory.
*/
public PluginClassLoader(String path) {
super(new URL[0], IJ.class.getClassLoader());
init(path);
}
/** This version of the constructor is used when ImageJ is launched using Java WebStart. */
public PluginClassLoader(String path, boolean callSuper) {
super(new URL[0], Thread.currentThread().getContextClassLoader());
init(path);
}
void init(String path) {
this.path = path;
//find all JAR files on the path and subdirectories
File f = new File(path);
try {
// Add plugin directory to search path
addURL(f.toURI().toURL());
} catch (MalformedURLException e) {
ij.IJ.log("PluginClassLoader: "+e);
}
String[] list = f.list();
if (list==null)
return;
for (int i=0; i