fixes #311

Author: wumpz

src/main/java/net/sf/jsqlparser/schema/Column.java

@@ -65,9 +65,13 @@ public String getFullyQualifiedName() {
         StringBuilder fqn = new StringBuilder();
 
         if (table != null) {
-            fqn.append(table.getFullyQualifiedName());
+            if (table.getAlias() != null) {
+                fqn.append(table.getAlias().getName());
+            } else {
+                fqn.append(table.getFullyQualifiedName());
+            }
         }
-        if (fqn.length()>0) {
+        if (fqn.length() > 0) {
             fqn.append('.');
         }
         if (columnName != null) {
@@ -85,4 +89,4 @@ public void accept(ExpressionVisitor expressionVisitor) {
     public String toString() {
         return getFullyQualifiedName();
     }
-}
+}

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

@@ -1,6 +1,9 @@
 package net.sf.jsqlparser.util;
 
+import java.util.Arrays;
+import java.util.List;
 import net.sf.jsqlparser.JSQLParserException;
+import net.sf.jsqlparser.expression.Alias;
 import net.sf.jsqlparser.expression.Expression;
 import net.sf.jsqlparser.expression.LongValue;
 import net.sf.jsqlparser.expression.operators.arithmetic.Addition;
@@ -99,4 +102,24 @@ public void testBuildSelectFromTableWithGroupBy() {
         assertEquals("SELECT * FROM mytable GROUP BY b", select.toString());
     }
 
+    @Test
+    public void testTableAliasIssue311() {
+        Table table1 = new Table("mytable1");
+        table1.setAlias(new Alias("tab1"));
+        Table table2 = new Table("mytable2");
+        table2.setAlias(new Alias("tab2"));
+
+        List<? extends Expression> colunas = Arrays.asList(new Column(table1, "col1"), new Column(table1, "col2"), new Column(table1, "col3"), new Column(table2, "b1"), new Column(table2, "b2"));
+
+        Select select = SelectUtils.buildSelectFromTableAndExpressions(table1, colunas.toArray(new Expression[colunas.size()]));
+
+        final EqualsTo equalsTo = new EqualsTo();
+        equalsTo.setLeftExpression(new Column(table1, "col1"));
+        equalsTo.setRightExpression(new Column(table2, "b1"));
+        Join addJoin = SelectUtils.addJoin(select, table2, equalsTo);
+        addJoin.setLeft(true);
+
+        assertEquals("SELECT tab1.col1, tab1.col2, tab1.col3, tab2.b1, tab2.b2 FROM mytable1 AS tab1 LEFT JOIN mytable2 AS tab2 ON tab1.col1 = tab2.b1",
+                    select.toString());
+    }
 }