private void testVersion() { String fileName = getBaseDir() + "/testVersion.h3"; FileUtils.delete(fileName); MVStore s; s = openStore(fileName); MVMap<String, String> m; s = openStore(fileName); m = s.openMap("data", String.class, String.class); long first = s.getCurrentVersion(); s.incrementVersion(); m.put("1", "Hello"); m.put("2", "World"); for (int i = 10; i < 20; i++) { m.put("" + i, "data"); } long old = s.getCurrentVersion(); s.incrementVersion(); m.put("1", "Hallo"); m.put("2", "Welt"); MVMap<String, String> mFirst; mFirst = m.openVersion(first); assertEquals(0, mFirst.size()); MVMap<String, String> mOld; assertEquals("Hallo", m.get("1")); assertEquals("Welt", m.get("2")); mOld = m.openVersion(old); assertEquals("Hello", mOld.get("1")); assertEquals("World", mOld.get("2")); assertTrue(mOld.isReadOnly()); s.getCurrentVersion(); s.setRetainChunk(0); long old2 = s.store(); // the old version is still available assertEquals("Hello", mOld.get("1")); assertEquals("World", mOld.get("2")); m.put("1", "Hi"); assertEquals("Welt", m.remove("2")); s.store(); s.close(); s = openStore(fileName); m = s.openMap("data", String.class, String.class); assertEquals("Hi", m.get("1")); assertEquals(null, m.get("2")); mOld = m.openVersion(old2); assertEquals("Hallo", mOld.get("1")); assertEquals("Welt", mOld.get("2")); s.close(); }
private void testExample() { String fileName = getBaseDir() + "/testExample.h3"; FileUtils.delete(fileName); // open the store (in-memory if fileName is null) MVStore s = MVStore.open(fileName); // create/get the map "data" // the String.class, String.class will be optional later MVMap<String, String> map = s.openMap("data", String.class, String.class); // add some data map.put("1", "Hello"); map.put("2", "World"); // get the current version, for later use long oldVersion = s.getCurrentVersion(); // from now on, the old version is read-only s.incrementVersion(); // more changes, in the new version // changes can be rolled back if required // changes always go into 'head' (the newest version) map.put("1", "Hi"); map.remove("2"); // access the old data (before incrementVersion) MVMap<String, String> oldMap = map.openVersion(oldVersion); // store the newest data to disk s.store(); // print the old version (can be done // concurrently with further modifications) // this will print Hello World // System.out.println(oldMap.get("1")); // System.out.println(oldMap.get("2")); oldMap.close(); // print the newest version ("Hi") // System.out.println(map.get("1")); // close the store - this doesn't write to disk s.close(); }