MapDB transaction overlap

TestTransactions.java

package net.emaze.mavenproject1;

import org.mapdb.DB;
import org.mapdb.DBMaker;
import org.mapdb.TxMaker;

import java.util.Map;
import org.junit.Test;

public class TestTransactions {

    @Test
    public void testSameCollectionInsertDifferentValuesInDifferentTransactions() throws Exception {

        TxMaker txMaker = DBMaker
                .newMemoryDB()
                .makeTxMaker();
        
        
        DB tx1 = txMaker.makeTx();
        DB tx2 = txMaker.makeTx();

        
        Map map1 = tx1.getTreeMap("testMap");
        
        map1.put(1, "asd");
        map1.put(2, "asd");
        
        tx1.commit();
        System.out.println("tx1 commit succeeded, map size after tx1 commits: " + txMaker.makeTx().getTreeMap("testMap").size());
        
        Map map2 = tx2.getTreeMap("testMap");
        map2.put(10000, "somevalue");
        
        // the following line throws a TxRollbackException
        tx2.commit();
        txMaker.close();
    }
    
    @Test
    public void testDifferentCollectionsInDifferentTransactions() throws Exception {

        TxMaker txMaker = DBMaker
                .newMemoryDB()
                .makeTxMaker();

        DB tx1 = txMaker.makeTx();
        DB tx2 = txMaker.makeTx();

        
        Map map1 = tx1.getTreeMap("testMap");
        
        map1.put(1, "asd");
        map1.put(2, "asd");
        
        tx1.commit();
        System.out.println("tx1 commit succeeded, map size after tx1 commits: " + txMaker.makeTx().getTreeMap("testMap").size());
        
        Map map2 = tx2.getTreeMap("otherMap");
        map2.put(20, "somevalue");
        
        // the following line throws a TxRollbackException
        tx2.commit();
        txMaker.close();
    }
    
    @Test
    public void testSameCollectionModifyDifferentValuesInDifferentTransactions() throws Exception {

        TxMaker txMaker = DBMaker
                .newMemoryDB()
                .makeTxMaker();
        
        DB txInit = txMaker.makeTx();
        txInit.getTreeMap("testMap").put(1, "value1");
        txInit.getTreeMap("testMap").put(2, "value2");
        txInit.commit();
        
        
        DB tx1 = txMaker.makeTx();
        DB tx2 = txMaker.makeTx();

        
        Map map1 = tx1.getTreeMap("testMap");
        
        map1.put(1, "asd");

        
        tx1.commit();
        System.out.println("tx1 commit succeeded, map size after tx1 commits: " + txMaker.makeTx().getTreeMap("testMap").size());
        
        Map map2 = tx2.getTreeMap("testMap");
        map2.put(2, "somevalue");
        
        // the following line throws a TxRollbackException
        tx2.commit();
        txMaker.close();
    }
    
    @Test
    public void testTransactionsDoingNothing() throws Exception {

        TxMaker txMaker = DBMaker
                .newMemoryDB()
                .makeTxMaker();
        
        DB txInit = txMaker.makeTx();
        txInit.getTreeMap("testMap").put(1, "value1");
        txInit.getTreeMap("testMap").put(2, "value2");
        txInit.commit();
        
        
        DB tx1 = txMaker.makeTx();
        DB tx2 = txMaker.makeTx();

        
        Map map1 = tx1.getTreeMap("testMap");
        
        tx1.commit();
        
        Map map2 = tx2.getTreeMap("testMap");
        
        // the following line throws a TxRollbackException
        tx2.commit();
        txMaker.close();
    }
    
}