doc: document the new Visitors

Signed-off-by: Andreas Reichel <[email protected]>

Author: manticore-projects

README.md

@@ -46,7 +46,7 @@ Assertions.assertEquals("b", b.getColumnName());
 }
 ```
 
-JSQLParser-4.9 is the last JDK8 compatible version and any future development will depend on JDK11.
+JSQLParser-4.9 is the last JDK8 compatible version. The upcoming JSQLParser-5.0 will depend on JDK11 and introduces API breaking changes to the AST Visitors. Please see the Migration Guide for the details.
 
 ## [Supported Grammar and Syntax](https://jsqlparser.github.io/JSqlParser/syntax.html)
 

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

@@ -1707,79 +1707,4 @@ public <S> StringBuilder visit(LambdaExpression lambdaExpression, S context) {
         lambdaExpression.getExpression().accept(this, context);
         return buffer;
     }
-
-    public void visit(ArrayExpression array) {
-        visit(array, null);
-    }
-
-    public void visit(ArrayConstructor aThis) {
-        visit(aThis, null);
-    }
-
-
-    public void visit(VariableAssignment var) {
-        visit(var, null);
-    }
-
-    public void visit(XMLSerializeExpr expr) {
-        visit(expr, null);
-    }
-
-    public void visit(TimezoneExpression var) {
-        visit(var, null);
-    }
-
-    public void visit(JsonAggregateFunction expression) {
-        visit(expression, null);
-    }
-
-    public void visit(JsonFunction expression) {
-        visit(expression, null);
-    }
-
-    public void visit(ConnectByRootOperator connectByRootOperator) {
-        visit(connectByRootOperator, null);
-    }
-
-    public void visit(OracleNamedFunctionParameter oracleNamedFunctionParameter) {
-        visit(oracleNamedFunctionParameter, null);
-    }
-
-    public void visit(AllColumns allColumns) {
-        visit(allColumns, null);
-    }
-
-    public void visit(AllTableColumns allTableColumns) {
-        visit(allTableColumns, null);
-    }
-
-    public void visit(AllValue allValue) {
-        visit(allValue, null);
-    }
-
-    public void visit(IsDistinctExpression isDistinctExpression) {
-        visit(isDistinctExpression, null);
-    }
-
-    public void visit(GeometryDistance geometryDistance) {
-        visit(geometryDistance, null);
-    }
-
-    public void visit(TSQLLeftJoin tsqlLeftJoin) {
-        visit(tsqlLeftJoin, null);
-    }
-
-    public void visit(TSQLRightJoin tsqlRightJoin) {
-        visit(tsqlRightJoin, null);
-    }
-
-    public void visit(StructType structType) {
-        visit(structType, null);
-    }
-
-    public void visit(LambdaExpression lambdaExpression) {
-        visit(lambdaExpression, null);
-    }
-
-
 }

src/site/sphinx/usage.rst

@@ -192,36 +192,38 @@ Traverse the Java Object Tree using the Visitor Patterns:
 
     // Define an Expression Visitor reacting on any Expression
     // Overwrite the visit() methods for each Expression Class
-    ExpressionVisitorAdapter expressionVisitorAdapter = new ExpressionVisitorAdapter() {
-        public void visit(EqualsTo equalsTo) {
-            equalsTo.getLeftExpression().accept(this);
-            equalsTo.getRightExpression().accept(this);
+    ExpressionVisitorAdapter<Void> expressionVisitorAdapter = new ExpressionVisitorAdapter<>() {
+        public <S> Void visit(EqualsTo equalsTo, S context) {
+            equalsTo.getLeftExpression().accept(this, context);
+            equalsTo.getRightExpression().accept(this, context);
+            return null;
         }
-        public void visit(Column column) {
+        public <S> Void visit(Column column, S context) {
             System.out.println("Found a Column " + column.getColumnName());
+            return null;
         }
     };
 
     // Define a Select Visitor reacting on a Plain Select invoking the Expression Visitor on the Where Clause
-    SelectVisitorAdapter selectVisitorAdapter = new SelectVisitorAdapter() {
+    SelectVisitorAdapter<Void> selectVisitorAdapter = new SelectVisitorAdapter<>() {
         @Override
-        public void visit(PlainSelect plainSelect) {
-            plainSelect.getWhere().accept(expressionVisitorAdapter);
+        public <S> Void visit(PlainSelect plainSelect, S context) {
+            return plainSelect.getWhere().accept(expressionVisitorAdapter, context);
         }
     };
 
     // Define a Statement Visitor for dispatching the Statements
-    StatementVisitorAdapter statementVisitor = new StatementVisitorAdapter() {
-        public void visit(Select select) {
-            select.getSelectBody().accept(selectVisitorAdapter);
+    StatementVisitorAdapter<Void> statementVisitor = new StatementVisitorAdapter<>() {
+        public <S> Void visit(Select select, S context) {
+            return select.getSelectBody().accept(selectVisitorAdapter, context);
         }
     };
 
     String sqlStr="select 1 from dual where a=b";
     Statement stmt = CCJSqlParserUtil.parse(sqlStr);
 
-    // Invoke the Statement Visitor
-    stmt.accept(statementVisitor);
+    // Invoke the Statement Visitor without a context
+    stmt.accept(statementVisitor, null);
 
 Find Table Names
 ==============================