From 89632aecbd40f973beca1ca84e409862f335481d Mon Sep 17 00:00:00 2001
From: Michael Bayne <mdb@threerings.net>
Date: Wed, 18 Jul 2001 21:16:12 +0000
Subject: [PATCH] Initial skeleton implementation of the resource manager.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@59 542714f4-19e9-0310-aa3c-eee0fc999fb1
---
 src/java/com/threerings/resource/Log.java     |  38 ++++++
 .../threerings/resource/ResourceManager.java  | 108 ++++++++++++++++++
 2 files changed, 146 insertions(+)
 create mode 100644 src/java/com/threerings/resource/Log.java
 create mode 100644 src/java/com/threerings/resource/ResourceManager.java

diff --git a/src/java/com/threerings/resource/Log.java b/src/java/com/threerings/resource/Log.java
new file mode 100644
index 000000000..d2f79e010
--- /dev/null
+++ b/src/java/com/threerings/resource/Log.java
@@ -0,0 +1,38 @@
+//
+// $Id: Log.java,v 1.1 2001/07/18 21:16:12 mdb Exp $
+
+package com.threerings.resource;
+
+/**
+ * A placeholder class that contains a reference to the log object used by
+ * the resource management package.
+ */
+public class Log
+{
+    public static com.samskivert.util.Log log =
+	new com.samskivert.util.Log("resource");
+
+    /** Convenience function. */
+    public static void debug (String message)
+    {
+	log.debug(message);
+    }
+
+    /** Convenience function. */
+    public static void info (String message)
+    {
+	log.info(message);
+    }
+
+    /** Convenience function. */
+    public static void warning (String message)
+    {
+	log.warning(message);
+    }
+
+    /** Convenience function. */
+    public static void logStackTrace (Throwable t)
+    {
+	log.logStackTrace(com.samskivert.util.Log.WARNING, t);
+    }
+}
diff --git a/src/java/com/threerings/resource/ResourceManager.java b/src/java/com/threerings/resource/ResourceManager.java
new file mode 100644
index 000000000..889eeb272
--- /dev/null
+++ b/src/java/com/threerings/resource/ResourceManager.java
@@ -0,0 +1,108 @@
+//
+// $Id: ResourceManager.java,v 1.1 2001/07/18 21:16:12 mdb Exp $
+
+package com.threerings.resource;
+
+import java.io.*;
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * The resource manager is responsible for maintaining a repository of
+ * resources that are synchronized with a remote source. This is
+ * accomplished in the form of a set of jar files that contain resources
+ * and that are updated from a remote resource repository via HTTP.
+ */
+public class ResourceManager
+{
+    /**
+     * Temporary means by which to construct a resource manager that loads
+     * resources from the specified source.
+     */
+    public ResourceManager (URL source)
+    {
+        _source = source;
+        _rootPath = _source.getPath();
+        // make root path end with a slash
+        if (!_rootPath.endsWith("/")) {
+            _rootPath = _rootPath + "/";
+        }
+    }
+
+    /**
+     * Fetches a resource from the local repository.
+     *
+     * @param path the path to the resource
+     * (ie. "config/miso.properties"). This should not begin with a slash.
+     *
+     * @exception IOException thrown if a problem occurs locating or
+     * reading the resource.
+     */
+    public InputStream getResource (String path)
+        throws IOException
+    {
+        try {
+            String rpath = _rootPath + path;
+            URL rurl = new URL(_source, rpath);
+            return rurl.openStream();
+
+        } catch (MalformedURLException mue) {
+            Log.warning("Unable to construct path to resource " +
+                        "[path=" + path + "].");
+            return null;
+        }
+    }
+
+    /**
+     * Fetches the requested resource and loads its contents into a byte
+     * array, which is returned. Note: this is hugely inefficient because
+     * the data is copied twice while reading and then once entirely again
+     * when a brand new byte array is returned for you, the caller (thanks
+     * to the inflexibility of <code>ByteArrayOutputStream</code>). Anyone
+     * reading a lot of resources should obtain an
+     * <code>InputStream</code> and read the data directly into where it
+     * needs to go.
+     *
+     * @exception IOException thrown if a problem occurs locating or
+     * reading the resource.
+     *
+     * @see #getResource
+     */
+    public byte[] getResourceAsBytes (String path)
+        throws IOException
+    {
+        InputStream in = getResource(path);
+        ByteArrayOutputStream out = new ByteArrayOutputStream();
+        byte[] buffer = new byte[512];
+
+        // i loathe to while(1), but we need a non-trivial loop condition
+        while (true) {
+            int bytes = in.read(buffer, 0, buffer.length);
+            if (bytes == 0) {
+                throw new IOException("Read zero bytes!?");
+            } else if (bytes < 0) {
+                break;
+            }
+            out.write(buffer, 0, bytes);
+        }
+
+        return out.toByteArray();
+    }
+
+    public static void main (String[] args)
+    {
+        try {
+            String root = System.getProperty("root", "");
+            URL url = new URL("file:" + root + "/rsrc");
+            ResourceManager rmgr = new ResourceManager(url);
+            byte[] data = rmgr.getResourceAsBytes("config/miso.properties");
+            System.out.println(new String(data));
+
+        } catch (Exception e) {
+            e.printStackTrace(System.err);
+        }
+    }
+
+    protected URL _source;
+    protected String _rootPath;
+}