/*
* Twidere - Twitter client for Android
*
* Copyright (C) 2012-2015 Mariotaku Lee <mariotaku.lee@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.getlantern.querybuilder;
/**
* Created by mariotaku on 15/1/12.
*/
public class Join implements SQLLang {
private final boolean natural;
private final Operation operation;
private final Selectable source;
private final Expression on;
public Join(boolean natural, Operation operation, Selectable source, Expression on) {
this.natural = natural;
this.operation = operation;
this.source = source;
this.on = on;
}
@Override
public String getSQL() {
if (operation == null) throw new IllegalArgumentException("operation can't be null!");
if (source == null) throw new IllegalArgumentException("source can't be null!");
final StringBuilder builder = new StringBuilder();
if (natural) {
builder.append("NATURAL ");
}
builder.append(operation.getSQL());
builder.append(" JOIN ");
builder.append(source.getSQL());
if (on != null) {
builder.append(" ON ");
builder.append(on.getSQL());
}
return builder.toString();
}
public enum Operation implements SQLLang {
LEFT("LEFT"), LEFT_OUTER("LEFT OUTER"), INNER("INNER"), CROSS("CROSS");
private final String op;
Operation(String op) {
this.op = op;
}
@Override
public String getSQL() {
return op;
}
}
}