refactor select parser 2nd version

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/dialect/mysql/MySQLSelectParser.java

@@ -39,23 +39,24 @@ public class MySQLSelectParser extends AbstractSelectParser {
     }
     
     @Override
-    public void query() {
-        if (getSqlParser().skipIfEqual(DefaultKeyword.SELECT)) {
-            parseDistinct();
-            getSqlParser().skipAll(MySQLKeyword.HIGH_PRIORITY, DefaultKeyword.STRAIGHT_JOIN, MySQLKeyword.SQL_SMALL_RESULT, MySQLKeyword.SQL_BIG_RESULT, MySQLKeyword.SQL_BUFFER_RESULT,
-                    MySQLKeyword.SQL_CACHE, MySQLKeyword.SQL_NO_CACHE, MySQLKeyword.SQL_CALC_FOUND_ROWS);
-            parseSelectList();
-            skipToFrom();
-        }
-        parseFrom();
-        parseWhere();
-        parseGroupBy();
-        parseOrderBy();
+    protected void parseBetweenSelectAndList() {
+        getSqlParser().skipAll(MySQLKeyword.HIGH_PRIORITY, DefaultKeyword.STRAIGHT_JOIN, MySQLKeyword.SQL_SMALL_RESULT, MySQLKeyword.SQL_BIG_RESULT, MySQLKeyword.SQL_BUFFER_RESULT,
+                MySQLKeyword.SQL_CACHE, MySQLKeyword.SQL_NO_CACHE, MySQLKeyword.SQL_CALC_FOUND_ROWS);
+    }
+    
+    @Override
+    protected final void skipToFrom() {
+        while (!getSqlParser().equalAny(DefaultKeyword.FROM) && !getSqlParser().equalAny(Assist.END)) {
+            getSqlParser().getLexer().nextToken();
+        }
+    }
+    
+    @Override
+    protected void customizedQuery() {
         parseLimit();
         if (getSqlParser().equalAny(DefaultKeyword.PROCEDURE)) {
             throw new SQLParsingUnsupportedException(getSqlParser().getLexer().getCurrentToken().getType());
         }
-        queryRest();
     }
     
     private void parseLimit() {
@@ -151,12 +152,6 @@ public class MySQLSelectParser extends AbstractSelectParser {
         return result;
     }
     
-    private void skipToFrom() {
-        while (!getSqlParser().equalAny(DefaultKeyword.FROM) && !getSqlParser().equalAny(Assist.END)) {
-            getSqlParser().getLexer().nextToken();
-        }
-    }
-    
     @Override
     protected void parseJoinTable() {
         if (getSqlParser().equalAny(DefaultKeyword.USING)) {

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/dialect/oracle/OracleSelectParser.java

@@ -33,26 +33,17 @@ public class OracleSelectParser extends AbstractSelectParser {
     }
     
     @Override
-    public void query() {
-        if (getSqlParser().skipIfEqual(DefaultKeyword.SELECT)) {
-            parseDistinct();
-            parseSelectList();
-        }
-        skipInto();
-        parseFrom();
-        parseWhere();
-        skipHierarchicalQueryClause();
-        parseGroupBy();
-        skipModelClause();
-        queryRest();
-    }
-    
-    private void skipInto() {
+    protected final void skipToFrom() {
         if (getSqlParser().equalAny(DefaultKeyword.INTO)) {
             throw new SQLParsingUnsupportedException(getSqlParser().getLexer().getCurrentToken().getType());
         }
     }
     
+    @Override
+    protected void customizedBetweenWhereAndGroupBy() {
+        skipHierarchicalQueryClause();
+    }
+    
     private void skipHierarchicalQueryClause() {
         skipConnect();
         skipStart();
@@ -77,6 +68,11 @@ public class OracleSelectParser extends AbstractSelectParser {
         }
     }
     
+    @Override
+    protected final void customizedBetweenGroupByAndOrderBy() {
+        skipModelClause();
+    }
+    
     private void skipModelClause() {
         if (!getSqlParser().skipIfEqual(OracleKeyword.MODEL)) {
             return;

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/dialect/postgresql/PostgreSQLSelectParser.java

@@ -39,22 +39,18 @@ public class PostgreSQLSelectParser extends AbstractSelectParser {
     }
     
     @Override
-    public void query() {
-        if (getSqlParser().skipIfEqual(DefaultKeyword.SELECT)) {
-            parseDistinct();
-            parseSelectList();
-            if (getSqlParser().skipIfEqual(DefaultKeyword.INTO)) {
-                getSqlParser().skipIfEqual(DefaultKeyword.TEMPORARY, PostgreSQLKeyword.TEMP, PostgreSQLKeyword.UNLOGGED);
-                getSqlParser().skipIfEqual(DefaultKeyword.TABLE);
-            }
+    protected final void skipToFrom() {
+        if (getSqlParser().skipIfEqual(DefaultKeyword.INTO)) {
+            getSqlParser().skipIfEqual(DefaultKeyword.TEMPORARY, PostgreSQLKeyword.TEMP, PostgreSQLKeyword.UNLOGGED);
+            getSqlParser().skipIfEqual(DefaultKeyword.TABLE);
         }
-        parseFrom();
-        parseWhere();
-        parseGroupBy();
+    }
+    
+    @Override
+    protected void customizedQuery() {
         if (getSqlParser().equalAny(PostgreSQLKeyword.WINDOW)) {
             throw new SQLParsingUnsupportedException(PostgreSQLKeyword.WINDOW);
         }
-        parseOrderBy();
         parseLimit();
         if (getSqlParser().skipIfEqual(DefaultKeyword.FETCH)) {
             throw new SQLParsingUnsupportedException(DefaultKeyword.FETCH);
@@ -66,7 +62,6 @@ public class PostgreSQLSelectParser extends AbstractSelectParser {
             }
             getSqlParser().skipIfEqual(PostgreSQLKeyword.NOWAIT);
         }
-        queryRest();
     }
     
     private void parseLimit() {

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/dialect/sqlserver/SQLServerSelectParser.java

@@ -42,19 +42,8 @@ public class SQLServerSelectParser extends AbstractSelectParser {
     }
     
     @Override
-    public void query() {
-        if (getSqlParser().skipIfEqual(DefaultKeyword.SELECT)) {
-            parseDistinct();
-            parseTop();
-            parseSelectList();
-        }
-        if (getSqlParser().equalAny(DefaultKeyword.INTO)) {
-            throw new SQLParsingUnsupportedException(getSqlParser().getLexer().getCurrentToken().getType());
-        }
-        parseFrom();
-        parseWhere();
-        parseGroupBy();
-        queryRest();
+    protected void parseBetweenSelectAndList() {
+        parseTop();
     }
     
     private void parseTop() {
@@ -112,6 +101,13 @@ public class SQLServerSelectParser extends AbstractSelectParser {
         return new CommonSelectItem("ROW_NUMBER", getSqlParser().parseAlias());
     }
     
+    @Override
+    protected final void skipToFrom() {
+        if (getSqlParser().equalAny(DefaultKeyword.INTO)) {
+            throw new SQLParsingUnsupportedException(getSqlParser().getLexer().getCurrentToken().getType());
+        }
+    }
+    
     @Override
     protected void parseJoinTable() {
         if (getSqlParser().skipIfEqual(DefaultKeyword.WITH)) {

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/statement/dql/select/AbstractSelectParser.java

@@ -85,7 +85,21 @@ public abstract class AbstractSelectParser implements SQLStatementParser {
         return selectStatement;
     }
     
-    protected abstract void query();
+    protected final void query() {
+        getSqlParser().getLexer().nextToken();
+        parseDistinct();
+        parseBetweenSelectAndList();
+        parseSelectList();
+        skipToFrom();
+        parseFrom();
+        parseWhere();
+        customizedBetweenWhereAndGroupBy();
+        parseGroupBy();
+        customizedBetweenGroupByAndOrderBy();
+        parseOrderBy();
+        customizedQuery();
+        queryRest();
+    }
     
     protected final void parseDistinct() {
         if (sqlParser.equalAny(DefaultKeyword.DISTINCT, DefaultKeyword.DISTINCTROW, DefaultKeyword.UNION)) {
@@ -104,6 +118,9 @@ public abstract class AbstractSelectParser implements SQLStatementParser {
         return false;
     }
     
+    protected void parseBetweenSelectAndList() {
+    }
+    
     protected final void parseSelectList() {
         do {
             parseSelectItem();
@@ -183,10 +200,7 @@ public abstract class AbstractSelectParser implements SQLStatementParser {
         return new CommonSelectItem(SQLUtil.getExactlyValue(expression.substring(0, expression.lastIndexOf(lastToken.getLiterals()))), Optional.of(lastToken.getLiterals()));
     }
     
-    protected void queryRest() {
-        if (sqlParser.equalAny(DefaultKeyword.UNION, DefaultKeyword.EXCEPT, DefaultKeyword.INTERSECT, DefaultKeyword.MINUS)) {
-            throw new SQLParsingUnsupportedException(sqlParser.getLexer().getCurrentToken().getType());
-        }
+    protected void skipToFrom() {
     }
     
     protected final void parseWhere() {
@@ -197,6 +211,12 @@ public abstract class AbstractSelectParser implements SQLStatementParser {
         parametersIndex = sqlParser.getParametersIndex();
     }
     
+    protected void customizedBetweenWhereAndGroupBy() {
+    }
+    
+    protected void customizedBetweenGroupByAndOrderBy() {
+    }
+    
     protected final void parseOrderBy() {
         if (!sqlParser.skipIfEqual(DefaultKeyword.ORDER)) {
             return;
@@ -370,6 +390,15 @@ public abstract class AbstractSelectParser implements SQLStatementParser {
         }
     }
     
+    protected void customizedQuery() {
+    }
+    
+    protected final void queryRest() {
+        if (sqlParser.equalAny(DefaultKeyword.UNION, DefaultKeyword.EXCEPT, DefaultKeyword.INTERSECT, DefaultKeyword.MINUS)) {
+            throw new SQLParsingUnsupportedException(sqlParser.getLexer().getCurrentToken().getType());
+        }
+    }
+    
     protected void customizedSelect() {
     }