/*
* Copyright 2004-2013 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.lealone.expression;
import org.lealone.dbobject.table.Column;
import org.lealone.dbobject.table.ColumnResolver;
import org.lealone.dbobject.table.TableFilter;
import org.lealone.engine.Session;
import org.lealone.util.StatementBuilder;
import org.lealone.value.Value;
import org.lealone.value.ValueArray;
/**
* A list of expressions, as in (ID, NAME).
* The result of this expression is an array.
*/
public class ExpressionList extends Expression {
private final Expression[] list;
public ExpressionList(Expression[] list) {
this.list = list;
}
public Value getValue(Session session) {
Value[] v = new Value[list.length];
for (int i = 0; i < list.length; i++) {
v[i] = list[i].getValue(session);
}
return ValueArray.get(v);
}
public int getType() {
return Value.ARRAY;
}
public void mapColumns(ColumnResolver resolver, int level) {
for (Expression e : list) {
e.mapColumns(resolver, level);
}
}
public Expression optimize(Session session) {
boolean allConst = true;
for (int i = 0; i < list.length; i++) {
Expression e = list[i].optimize(session);
if (!e.isConstant()) {
allConst = false;
}
list[i] = e;
}
if (allConst) {
return ValueExpression.get(getValue(session));
}
return this;
}
public void setEvaluatable(TableFilter tableFilter, boolean b) {
for (Expression e : list) {
e.setEvaluatable(tableFilter, b);
}
}
public int getScale() {
return 0;
}
public long getPrecision() {
return Integer.MAX_VALUE;
}
public int getDisplaySize() {
return Integer.MAX_VALUE;
}
public String getSQL(boolean isDistributed) {
StatementBuilder buff = new StatementBuilder("(");
for (Expression e : list) {
buff.appendExceptFirst(", ");
buff.append(e.getSQL(isDistributed));
}
if (list.length == 1) {
buff.append(',');
}
return buff.append(')').toString();
}
public void updateAggregate(Session session) {
for (Expression e : list) {
e.updateAggregate(session);
}
}
public boolean isEverything(ExpressionVisitor visitor) {
for (Expression e : list) {
if (!e.isEverything(visitor)) {
return false;
}
}
return true;
}
public int getCost() {
int cost = 1;
for (Expression e : list) {
cost += e.getCost();
}
return cost;
}
public Expression[] getExpressionColumns(Session session) {
ExpressionColumn[] expr = new ExpressionColumn[list.length];
for (int i = 0; i < list.length; i++) {
Expression e = list[i];
Column col = new Column("C" + (i + 1), e.getType(), e.getPrecision(), e.getScale(), e.getDisplaySize());
expr[i] = new ExpressionColumn(session.getDatabase(), col);
}
return expr;
}
}