improve wall filter

src/main/java/com/alibaba/druid/sql/parser/EOFParserException.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright 1999-2011 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.druid.sql.parser;
+
+@SuppressWarnings("serial")
+public class EOFParserException extends ParserException {
+
+    public EOFParserException(){
+        super("EOF");
+    }
+}

src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java

@@ -457,8 +457,10 @@ public class SQLExprParser extends SQLParser {
                 sqlExpr = new SQLIdentifierExpr('"' + lexer.stringVal() + '"');
                 lexer.nextToken();
                 break;
+            case EOF:
+                throw new EOFParserException();
             default:
-                throw new ParserException("ERROR. token : " + tok + " " + lexer.stringVal());
+                throw new ParserException("ERROR. token : " + tok + ", pos : " + lexer.pos());
         }
 
         return primaryRest(sqlExpr);
@@ -814,8 +816,11 @@ public class SQLExprParser extends SQLParser {
         SQLExpr rightExp;
         if (lexer.token() == Token.EQ) {
             lexer.nextToken();
-            rightExp = bitOr();
-
+            try {
+                rightExp = bitOr();
+            } catch (EOFParserException e) {
+                throw new ParserException("EOF, " + expr + "=", e);
+            }
             rightExp = equalityRest(rightExp);
 
             expr = new SQLBinaryOpExpr(expr, SQLBinaryOperator.Equality, rightExp);

src/main/java/com/alibaba/druid/sql/parser/SQLStatementParser.java

@@ -223,7 +223,7 @@ public class SQLStatementParser extends SQLParser {
                 continue;
             }
 
-            throw new ParserException("TODO " + lexer.token() + " " + lexer.stringVal() + ", pos " + lexer.pos());
+            throw new ParserException("syntax error, " + lexer.token() + " " + lexer.stringVal() + ", pos " + lexer.pos());
         }
     }