Add support for JOIN FETCH

Author: dengliming

src/main/java/net/sf/jsqlparser/statement/select/Join.java

@@ -37,6 +37,7 @@ public class Join extends ASTNodeAccessImpl {
     private boolean semi = false;
     private boolean straight = false;
     private boolean apply = false;
+    private boolean fetch = false;
     private FromItem fromItem;
     private KSQLJoinWindow joinWindow;
 
@@ -149,6 +150,24 @@ public Join withApply(boolean apply) {
         return this;
     }
 
+    /**
+     * Whether is a "FETCH" join (JPQL/HQL)
+     *
+     * @return true if is a "FETCH" join
+     */
+    public boolean isFetch() {
+        return fetch;
+    }
+
+    public void setFetch(boolean b) {
+        fetch = b;
+    }
+
+    public Join withFetch(boolean b) {
+        this.setFetch(b);
+        return this;
+    }
+
     /**
      * Whether is a "SEMI" join
      *
@@ -429,6 +448,9 @@ public String toString() {
                     builder.append(joinHint).append(" ");
                 }
                 builder.append("JOIN ");
+                if (fetch) {
+                    builder.append("FETCH ");
+                }
             }
 
             builder.append(fromItem).append((joinWindow != null) ? " WITHIN " + joinWindow : "");

src/main/java/net/sf/jsqlparser/util/deparser/SelectDeParser.java

@@ -616,6 +616,9 @@ public void deparseJoin(Join join) {
                     builder.append(" ").append(join.getJoinHint());
                 }
                 builder.append(" JOIN ");
+                if (join.isFetch()) {
+                    builder.append("FETCH ");
+                }
             }
 
         }

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -4971,7 +4971,11 @@ Join JoinerExpression() #JoinerExpression:
     ]
 
     (
-        ( [ joinHint=JoinHint() {join.setJoinHint(joinHint); } ] <K_JOIN> )
+        (
+            [ joinHint=JoinHint() {join.setJoinHint(joinHint); } ]
+            <K_JOIN>
+            [ <K_FETCH> { join.setFetch(true); } ]
+        )
         |
         "," { join.setSimple(true); } (<K_OUTER> { join.setOuter(true); } )?
         |

src/test/java/net/sf/jsqlparser/statement/select/SelectTest.java

@@ -1210,6 +1210,12 @@ public void testJoin() throws JSQLParserException {
         assertEquals("b", plainSelect.getJoins().get(0).getFromItem().getAlias().getName());
     }
 
+    @Test
+    public void testJoinFetch() throws JSQLParserException {
+        String statement = "SELECT c FROM Customer c LEFT JOIN FETCH c.orders o";
+        assertSqlCanBeParsedAndDeparsed(statement, true);
+    }
+
     @Test
     public void testFunctions() throws JSQLParserException {
         String statement = "SELECT MAX(id) AS max FROM mytable WHERE mytable.col = 9";