package com.avaje.ebeaninternal.server.query;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import com.avaje.ebean.bean.EntityBean;
import com.avaje.ebeaninternal.server.deploy.BeanPropertyAssoc;
import com.avaje.ebeaninternal.server.deploy.BeanPropertyAssocMany;
import com.avaje.ebeaninternal.server.deploy.DbReadContext;
import com.avaje.ebeaninternal.server.deploy.DbSqlContext;
import com.avaje.ebeaninternal.server.deploy.TableJoin;
/**
* The purpose is to add an extra join to the query.
* <p>
* This is used to support the where clause or order by clause that refers
* to properties that are NOT included in the select. To support the where clause
* etc in this case we must add an extra join.
* </p>
*/
public class SqlTreeNodeExtraJoin implements SqlTreeNode {
private final BeanPropertyAssoc<?> assocBeanProperty;
private final String prefix;
private final boolean manyJoin;
private List<SqlTreeNodeExtraJoin> children;
public SqlTreeNodeExtraJoin(String prefix, BeanPropertyAssoc<?> assocBeanProperty) {
this.prefix = prefix;
this.assocBeanProperty = assocBeanProperty;
this.manyJoin = assocBeanProperty instanceof BeanPropertyAssocMany<?>;
}
public void buildSelectExpressionChain(List<String> selectChain) {
// nothing to add
}
/**
* Return true if the extra join is a many join.
* <p>
* This means we need to add distinct to the sql query.
* </p>
*/
public boolean isManyJoin() {
return manyJoin;
}
public String getName() {
return prefix;
}
public void addChild(SqlTreeNodeExtraJoin child){
if (children == null){
children = new ArrayList<SqlTreeNodeExtraJoin>();
}
children.add(child);
}
public void appendFrom(DbSqlContext ctx, SqlJoinType joinType) {
boolean manyToMany = false;
if (assocBeanProperty instanceof BeanPropertyAssocMany<?>){
BeanPropertyAssocMany<?> manyProp = (BeanPropertyAssocMany<?>)assocBeanProperty;
if (manyProp.isManyToMany()){
manyToMany = true;
String alias = ctx.getTableAlias(prefix);
String[] split = SplitName.split(prefix);
String parentAlias = ctx.getTableAlias(split[0]);
String alias2 = alias+"z_";
TableJoin manyToManyJoin = manyProp.getIntersectionTableJoin();
manyToManyJoin.addJoin(joinType, parentAlias, alias2, ctx);
assocBeanProperty.addJoin(joinType, alias2, alias, ctx);
}
}
if (!manyToMany){
assocBeanProperty.addJoin(joinType, prefix, ctx);
}
if (children != null) {
if (manyJoin) {
// if AUTO then make all decendants use OUTER JOIN
joinType = joinType.autoToOuter();
}
for (int i = 0; i < children.size(); i++) {
SqlTreeNodeExtraJoin child = children.get(i);
child.appendFrom(ctx, joinType);
}
}
}
/**
* Does nothing.
*/
public void appendSelect(DbSqlContext ctx, boolean subQuery) {
}
/**
* Does nothing.
*/
public void appendWhere(DbSqlContext ctx) {
}
/**
* Does nothing.
*/
public void load(DbReadContext ctx, EntityBean parentBean) throws SQLException {
}
}