Changeset 22973 for main/trunk/greenstone3/src/java/org/greenstone/gsdl3/util/JDBMWrapper.java

Timestamp:

2010-09-28T10:18:57+13:00 (14 years ago)

Author:

davidb

Message:

Code changed to use Class.forName to dynamically load required database wrapper class (e.g. GDBMWrapper or JDBMWrapper). This is so the code can be compiled up with some of these database wrapper classes optionally switched out (e.g. name changed to .java.tmp). Additional routine also added to test is a database is open. In JDBMWrapper, the close routine was modified so it only closes the database one. Our code seems to call 'cleanup' more than once, and letting it close a JDBMWrapper class a second time throws an exception deep within JDBM implementation.

File:

• main/trunk/greenstone3/src/java/org/greenstone/gsdl3/util/JDBMWrapper.java (modified) (5 diffs)

main/trunk/greenstone3/src/java/org/greenstone/gsdl3/util/JDBMWrapper.java

@@ -43 +43 @@
     static String TNAME = "greenstone";
 
-    RecordManager  recman_;
+    RecordManager  recman_ = null;
     HTree          hashtable_;
+
+    String db_filename_;
 
     static private PrintWriter utf8out = null;
@@ -74 +76 @@
       // => assume the database must exist
       boolean must_exist = true; // default
-      
+
+      if (recman_ != null) {
+      String message = "openDatabase() called when the class already has a database open\n";
+      message += "  Use closeDatabase before opening the next one.\n";
+      message += "  Existing database file: " + db_filename_ + "\n";
+      message += "  New database file:      " + db_filename + "\n";
+      logger.warn(message);
+      // consider closing it automatically?
+      }
+
+
       try {
       // create or open a record manager
@@ -91 +103 @@
           if (must_exist) {
           recman_.close();
+          recman_ = null;
+          db_filename_ = null;
+
           System.err.println("Database table '" + TNAME +"' does not exist.");
           throw new IOException();
@@ -106 +121 @@
       }
 
+      db_filename_ = db_filename;
 
       return true;
@@ -114 +130 @@
   public void closeDatabase() {
       try {
-      recman_.close();
+      if (recman_ != null) {
+          recman_.close();
+          recman_ = null;
+          db_filename_ = null;
+      }
       }
       catch (IOException e) {