mysql select * frm aaa limit 20xxx ，limit后的字符串无法转换为数字的处理

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

@@ -15,6 +15,8 @@
  */
 package com.alibaba.druid.sql.parser;
 
+import com.alibaba.druid.util.StringUtils;
+
 import static com.alibaba.druid.sql.parser.CharTypes.isFirstIdentifierChar;
 import static com.alibaba.druid.sql.parser.CharTypes.isIdentifierChar;
 import static com.alibaba.druid.sql.parser.CharTypes.isWhitespace;
@@ -1147,7 +1149,11 @@ public class Lexer {
     }
 
     public BigDecimal decimalValue() {
-        return new BigDecimal(subString(mark, bufPos).toCharArray());
+        String value = subString(mark, bufPos);
+        if (!StringUtils.isNumeric(value)){
+            throw new ParserException(value+" is not a number!");
+        }
+        return new BigDecimal(value.toCharArray());
     }
 
     public static interface CommentHandler {

src/main/java/com/alibaba/druid/util/StringUtils.java

@@ -95,7 +95,7 @@ public class StringUtils {
         return a.equalsIgnoreCase(b);
     }
 
-    public static boolean isEmpty(String value) {
+    public static boolean isEmpty(CharSequence value) {
         if (value == null || value.length() == 0) {
             return true;
         }
@@ -119,4 +119,18 @@ public class StringUtils {
         }
         return h;
     }
+
+    public static boolean isNumeric(final CharSequence cs) {
+        if (isEmpty(cs)) {
+            return false;
+        }
+        final int sz = cs.length();
+        for (int i = 0; i < sz; i++) {
+            if (!Character.isDigit(cs.charAt(i))) {
+                return false;
+            }
+        }
+        return true;
+    }
+
 }

src/test/java/com/alibaba/druid/mysql/MysqlLimitTest.java

@@ -0,0 +1,28 @@
+package com.alibaba.druid.mysql;
+
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.parser.SQLParserUtils;
+import com.alibaba.druid.sql.parser.SQLStatementParser;
+import junit.framework.TestCase;
+
+import java.util.List;
+
+/**
+ * Created by tianzhen.wtz on 2016/6/7.
+ * 类说明：
+ */
+public class MysqlLimitTest extends TestCase{
+
+
+    public void testLimit(){
+        String sql = "select * from aaa limit 20exx";
+        SQLStatementParser statementParser = SQLParserUtils.createSQLStatementParser(sql, "mysql");
+        try {
+            List<SQLStatement> sqlStatements = statementParser.parseStatementList();
+        } catch (Exception e) {
+            assertTrue(e.getMessage().contains("is not a number!"));
+        }
+
+
+    }
+}