/*
 *    Copyright 2016-2020 the original author or authors.
 *
 *    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 org.mybatis.dynamic.sql.render;

import java.util.Map;
import java.util.Optional;

import org.mybatis.dynamic.sql.SqlTable;

/**
 * Returns the alias for a table if specified, or the table name itself.
 * This is useful for join rendering when we always want to have an alias for the table.
 *
 * @author Jeff Butler
 *
 */
public class GuaranteedTableAliasCalculator extends TableAliasCalculator {

    private GuaranteedTableAliasCalculator(Map<SqlTable, String> aliases) {
        super(aliases);
    }

    @Override
    public Optional<String> aliasForColumn(SqlTable table) {
        return super.aliasForColumn(table)
                .map(Optional::of)
                .orElseGet(() -> Optional.of(table.tableNameAtRuntime()));
    }

    public static TableAliasCalculator of(Map<SqlTable, String> aliases) {
        return new GuaranteedTableAliasCalculator(aliases);
    }
}

@@ -20,17 +20,17 @@
 2016-202
-0
+1
  the ori
@@ -1240,22 +1240,40 @@
         
-return
+Optional%3CString%3E alias =
  super.a
@@ -1292,16 +1292,17 @@
 n(table)
+;
 %0A       
@@ -1306,67 +1306,94 @@
     
-        .map(Optional::of)%0A                .orElseGet(() -%3E
+if (alias.isPresent()) %7B%0A            return alias;%0A        %7D else %7B%0A            return
  Opt
@@ -1428,18 +1428,27 @@
 ntime())
-)
 ;
+%0A        %7D
 %0A    %7D%0A%0A

Remove unnecessary unbox/rebox