fixes #194

Author: wumpz

README.md

@@ -38,6 +38,7 @@ Also I would like to know about needed examples or documentation stuff.
 
 ## Extensions in the latest SNAPSHOT version 0.9.5
 
+* support for **insert ... on duplicate key update**
 * improved support for **alter table** statements
 * first Oracle hint support for **select** statements 
 * first **alter table foreign key** support

src/main/java/net/sf/jsqlparser/util/TablesNamesFinder.java

@@ -51,7 +51,7 @@
 /**
  * Find all used tables within an select statement.
  */
-public class TablesNamesFinder implements SelectVisitor, FromItemVisitor, ExpressionVisitor, ItemsListVisitor, SelectItemVisitor, StatementVisitor  {
+public class TablesNamesFinder implements SelectVisitor, FromItemVisitor, ExpressionVisitor, ItemsListVisitor, SelectItemVisitor, StatementVisitor {
 
     private List<String> tables;
     /**
@@ -136,7 +136,7 @@ public List<String> getTableList(CreateTable create) {
         create.accept(this);
         return tables;
     }
-    
+
     public List<String> getTableList(Expression expr) {
         init();
         expr.accept(this);
@@ -157,7 +157,9 @@ public void visit(PlainSelect plainSelect) {
             }
         }
 
-        plainSelect.getFromItem().accept(this);
+        if (plainSelect.getFromItem() != null) {
+            plainSelect.getFromItem().accept(this);
+        }
 
         if (plainSelect.getJoins() != null) {
             for (Join join : plainSelect.getJoins()) {
@@ -624,18 +626,18 @@ public void visit(RowConstructor rowConstructor) {
         }
     }
 
-	@Override
-	public void visit(HexValue hexValue) {
-		
-	}
+    @Override
+    public void visit(HexValue hexValue) {
+
+    }
 
     @Override
     public void visit(Merge merge) {
         throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
     }
-    
+
     @Override
     public void visit(OracleHint hint) {
     }
-    
+
 }

src/test/java/net/sf/jsqlparser/util/TablesNamesFinderTest.java

@@ -351,7 +351,17 @@ public void visit(OracleHint hint) {
         };
         tablesNamesFinder.getTableList(select);
         assertNull(holder[0]);
-
     }
+    
+    @Test
+	public void testGetTableListIssue194() throws Exception {
+		String sql = "SELECT 1";
+		net.sf.jsqlparser.statement.Statement statement = pm.parse(new StringReader(sql));
+
+		Select selectStatement = (Select) statement;
+		TablesNamesFinder tablesNamesFinder = new TablesNamesFinder();
+		List<String> tableList = tablesNamesFinder.getTableList(selectStatement);
+		assertEquals(0, tableList.size());
+	}
 
 }