Java tutorial
/** * The contents of this file are subject to the license and copyright * detailed in the LICENSE and NOTICE files at the root of the source * tree and available online at * * http://www.dspace.org/license/ */ package org.dspace.servicemanager.spring; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.util.ArrayList; import java.util.List; import java.util.Arrays; import org.dspace.servicemanager.config.DSpaceConfigurationService; import org.springframework.core.io.ClassPathResource; import org.springframework.core.io.FileSystemResource; import org.springframework.core.io.Resource; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Takes a list of paths to resources and turns them into different * things (file/IS/resource). * This also allows us to look on a relative or absolute path and will * automatically check the typical places one might expect to put DSpace * config files. * * @author Aaron Zeckoski (aaron@caret.cam.ac.uk) */ public class ResourceFinder { private static Logger log = LoggerFactory.getLogger(ResourceFinder.class); public static final String relativePath = DSpaceConfigurationService.DSPACE + "/"; public static final String environmentPathVariable = DSpaceConfigurationService.DSPACE_HOME; private static List<Resource> makeResources(List<String> paths) { List<Resource> rs = new ArrayList<Resource>(); if (paths != null && !paths.isEmpty()) { for (String path : paths) { try { Resource r = makeResource(path); rs.add(r); } catch (IllegalArgumentException e) { // do not add if not found, just skip log.error(e.getMessage() + ", continuing..."); } } } return rs; } private static Resource makeResource(String path) { if (path.startsWith("/")) { path = path.substring(1); } Resource r = findResource(path); if (!r.exists()) { // try to find just the fileName // get the fileName from the path int fileStart = path.lastIndexOf('/') + 1; String fileName = path.substring(fileStart); r = findResource(fileName); } // try the environment path first if (!r.exists()) { throw new IllegalArgumentException( "Could not find this resource (" + path + ") in any of the checked locations"); } return r; } private static Resource findResource(String path) { Resource r; String envPath = getEnvironmentPath() + path; r = new FileSystemResource(envPath); if (!r.exists()) { // try the relative path next String relPath = getRelativePath() + path; r = new FileSystemResource(relPath); if (!r.exists()) { // now try the classloaders ClassLoader cl = ResourceFinder.class.getClassLoader(); r = new ClassPathResource(path, cl); if (!r.exists()) { // finally try the context classloader cl = Thread.currentThread().getContextClassLoader(); r = new ClassPathResource(path, cl); } } } return r; } /** * Resolves a list of paths into resources relative to environmental * defaults or relative paths or the classloader. * * @param paths a list of paths to resources (org/sakaiproject/mystuff/Thing.xml) * @return an array of Spring Resource objects */ public static Resource[] getResources(List<String> paths) { return makeResources(paths).toArray(new Resource[paths.size()]); } public static File[] getFiles(List<String> paths) { List<Resource> rs = makeResources(paths); File[] files = new File[rs.size()]; for (int i = 0; i < rs.size(); i++) { Resource r = rs.get(i); try { files[i] = r.getFile(); } catch (IOException e) { throw new RuntimeException("Failed to get file for: " + r.getFilename(), e); } } return files; } public static InputStream[] getInputStreams(List<String> paths) { List<Resource> rs = makeResources(paths); InputStream[] streams = new InputStream[rs.size()]; for (int i = 0; i < rs.size(); i++) { Resource r = rs.get(i); try { streams[i] = r.getInputStream(); } catch (IOException e) { throw new RuntimeException("Failed to get inputstream for: " + r.getFilename(), e); } } return streams; } /** * Resolve a path into a resource relative to environmental defaults * or relative paths or the classloader. * * @param path a path to a resource (org/dspace/mystuff/Thing.xml) * @return the Spring Resource object * @throws IllegalArgumentException if no resource can be found */ public static Resource getResource(String path) { if (path == null) { throw new IllegalArgumentException("Invalid null path"); } return makeResource(path); } /** * Attempt to resolve multiple paths in order until one is found. * * @param paths an array of paths to a resource (org/dspace/mystuff/Thing.xml) * @return the Spring Resource object * @throws IllegalArgumentException if no resource can be found */ public static Resource getResourceFromPaths(String[] paths) { if (paths == null) { throw new IllegalArgumentException("Invalid null paths"); } Resource r = null; for (String path : paths) { try { r = makeResource(path); } catch (IllegalArgumentException e) { continue; } break; } if (r == null) { throw new IllegalArgumentException("Could not find any resource from paths (" + Arrays.toString(paths) + ") in any of the checked locations"); } return r; } public static File getFile(String path) { Resource r = getResource(path); File f = null; try { f = r.getFile(); } catch (IOException e) { throw new RuntimeException("Failed to get file for: " + r.getFilename(), e); } return f; } public static InputStream getInputStream(String path) { Resource r = getResource(path); InputStream is = null; try { is = r.getInputStream(); } catch (IOException e) { throw new RuntimeException("Failed to get inputstream for: " + r.getFilename(), e); } return is; } protected static String getRelativePath() { File currentPath = new File(""); File f = new File(currentPath, relativePath); if (!f.exists() || !f.isDirectory()) { f = new File(currentPath, DSpaceConfigurationService.DSPACE); if (!f.exists() || !f.isDirectory()) { f = currentPath; } } String absPath = f.getAbsolutePath(); if (!absPath.endsWith(File.separatorChar + "")) { absPath += File.separatorChar; } return absPath; } protected static String getEnvironmentPath() { String envPath = System.getenv(environmentPathVariable); if (envPath == null) { envPath = System.getProperty(environmentPathVariable); if (envPath == null) { String container = getContainerHome(); if (container == null) { container = ""; } envPath = container + File.separatorChar + DSpaceConfigurationService.DSPACE + File.separatorChar; } } return envPath; } /** * If running in Tomcat, get its home directory. * * @return the container home if one can be found */ public static String getContainerHome() { String catalina = System.getProperty("catalina.base"); if (catalina == null) { catalina = System.getProperty("catalina.home"); } return catalina; } }