001/**
002 * Copyright (c) 2022-2023, Mybatis-Flex (fuhai999@gmail.com).
003 * <p>
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 * <p>
008 * http://www.apache.org/licenses/LICENSE-2.0
009 * <p>
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package com.mybatisflex.core.query;
017
018import com.mybatisflex.core.dialect.IDialect;
019
020import java.io.Serializable;
021import java.util.ArrayList;
022import java.util.List;
023import java.util.function.Supplier;
024
025/**
026 * @author michael yang (fuhai999@gmail.com)
027 * @Date: 2020/1/14
028 */
029public class Join implements Serializable {
030
031    private static final long serialVersionUID = 1L;
032
033    static final String TYPE_LEFT = " LEFT JOIN ";
034    static final String TYPE_RIGHT = " RIGHT JOIN ";
035    static final String TYPE_INNER = " INNER JOIN ";
036    static final String TYPE_FULL = " FULL JOIN ";
037    static final String TYPE_CROSS = " CROSS JOIN ";
038
039
040    private String type;
041    private QueryTable queryTable;
042    private QueryCondition on;
043    private boolean effective;
044
045    public Join(String type, String table, boolean when) {
046        this.type = type;
047        this.queryTable = new QueryTable(table);
048        this.effective = when;
049    }
050
051    public Join(String type, QueryWrapper queryWrapper, boolean when) {
052        this.type = type;
053        this.queryTable = new SelectQueryTable(queryWrapper);
054        this.effective = when;
055    }
056
057
058
059    QueryTable getQueryTable() {
060        return queryTable;
061    }
062
063
064    public void on(QueryCondition condition) {
065        this.on = condition;
066    }
067
068    QueryCondition getOnCondition(){
069        return on;
070    }
071
072    public boolean checkEffective() {
073        return effective;
074    }
075
076    public void when(boolean when) {
077        this.effective = when;
078    }
079
080    public void when(Supplier<Boolean> fn) {
081        this.effective = fn.get();
082    }
083
084    public String toSql(List<QueryTable> queryTables, IDialect dialect) {
085        //left join, right join,  inner join ...
086        StringBuilder sql = new StringBuilder(type);
087        sql.append(queryTable.toSql(dialect));
088
089        //left join xxx as xxx2 on xxx2.id = xxx3.other
090        List<QueryTable> newQueryTables = new ArrayList<>(queryTables);
091        newQueryTables.add(queryTable);
092        sql.append(" ON ").append(on.toSql(newQueryTables, dialect));
093        return sql.toString();
094    }
095}