[Mulgara-svn] r1964 - trunk/src/jar/util/java/org/mulgara/util/io

[pag at mulgara.org]

Author: pag
Date: 2010-07-03 02:14:25 +0000 (Sat, 03 Jul 2010)
New Revision: 1964

Modified:
   trunk/src/jar/util/java/org/mulgara/util/io/LBufferedFile.java
Log:
Add a factory method that detects the system settings to determine the file access mode

Modified: trunk/src/jar/util/java/org/mulgara/util/io/LBufferedFile.java
===================================================================
--- trunk/src/jar/util/java/org/mulgara/util/io/LBufferedFile.java	2010-07-03 01:22:24 UTC (rev 1963)
+++ trunk/src/jar/util/java/org/mulgara/util/io/LBufferedFile.java	2010-07-03 02:14:25 UTC (rev 1964)
@@ -35,9 +35,15 @@
   /** The property for the block type. May be "direct" or "javaHeap" */
   public static final String MEM_TYPE_PROP = "mulgara.xa.memoryType";
 
+  /** The property for the io type. May be "mapped" or "explicit" */
+  public static final String IO_TYPE_PROP = "mulgara.xa.forceIOType";
+
   /** Enumeration of the different memory types for blocks */
   enum BlockMemoryType { DIRECT, HEAP };
 
+  /** Enumeration of the different io types */
+  enum IOType { MAPPED, EXPLICIT };
+
   /** Native ordering of the bytes */
   ByteOrder NATIVE_ORDER = ByteOrder.nativeOrder();
 
@@ -47,6 +53,8 @@
   /** The configured type of block type to use. */
   private static final BlockMemoryType BLOCK_TYPE;
 
+  private static final IOType ioType;
+
   static {
     String defBlockType = System.getProperty(MEM_TYPE_PROP, DEFAULT.name());
     if (defBlockType.equalsIgnoreCase(BlockMemoryType.DIRECT.name())) {
@@ -57,6 +65,18 @@
       logger.warn("Invalid value for property " + MEM_TYPE_PROP + ": " + defBlockType);
       BLOCK_TYPE = DEFAULT;
     }
+
+    String forceIOTypeProp = System.getProperty("mulgara.xa.forceIOType", "mapped");
+
+    if (forceIOTypeProp.equalsIgnoreCase(IOType.MAPPED.name())) {
+      ioType = IOType.MAPPED;
+    } else if (forceIOTypeProp.equalsIgnoreCase(IOType.EXPLICIT.name())) {
+      ioType = IOType.EXPLICIT;
+    } else {
+      logger.warn("Invalid value for property mulgara.xa.forceIOType: " + forceIOTypeProp);
+      ioType = IOType.MAPPED;
+    }
+
   }
 
 
@@ -101,6 +121,13 @@
   public abstract void seek(long offset) throws IOException;
 
   /**
+   * Closes the file resource.
+   */
+  public void close() throws IOException {
+    file.close();
+  }
+
+  /**
    * Ensures that all data written to this file is forced to disk.
    * @throws IOException If there is an IO error accessing the disk.
    */
@@ -109,6 +136,32 @@
   }
 
   /**
+   * Create a buffered file using a filename.
+   * @param fileName The name of the file to provide buffered access to.
+   * @return The readonly buffered file.
+   * @throws IOException An error opening the file.
+   */
+  public static LBufferedFile createReadOnlyLBufferedFile(String fileName) throws IOException {
+    return createReadOnlyLBufferedFile(new RandomAccessFile(fileName, "r"));
+  }
+
+  /**
+   * Create a buffered file, taking over the RandomAccessFile that is provided.
+   * @param f The file to provide buffered access to.
+   * @return The readonly buffered file.
+   * @throws IOException An error opening the file.
+   */
+  public static LBufferedFile createReadOnlyLBufferedFile(RandomAccessFile f) throws IOException {
+    if (ioType == IOType.MAPPED) {
+      return new LMappedBufferedFile(f);
+    } else if (ioType == IOType.EXPLICIT) {
+      return new LReadOnlyIOBufferedFile(f);
+    } else {
+      throw new IllegalArgumentException("Invalid BlockFile ioType.");
+    }
+  }
+
+  /**
    * Allocates data according to the system configured memory model.
    * @param size The number of bytes in the allocated buffer.
    * @return the allocated buffer.