/**
* Copyright (C) 2009-2013 FoundationDB, LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.foundationdb.server.types.common.funcs;
import java.util.List;
import com.foundationdb.server.types.LazyList;
import com.foundationdb.server.types.TClass;
import com.foundationdb.server.types.TCustomOverloadResult;
import com.foundationdb.server.types.TExecutionContext;
import com.foundationdb.server.types.TInstance;
import com.foundationdb.server.types.TOverloadResult;
import com.foundationdb.server.types.TPreptimeContext;
import com.foundationdb.server.types.TPreptimeValue;
import com.foundationdb.server.types.TScalar;
import com.foundationdb.server.types.texpressions.TInputSetBuilder;
import com.foundationdb.server.types.texpressions.TScalarBase;
import com.foundationdb.server.types.value.ValueSource;
import com.foundationdb.server.types.value.ValueTarget;
import com.foundationdb.util.Strings;
public class Repeat extends TScalarBase {
private final TClass stringType;
private final TClass intType;
public Repeat (TClass stringType, TClass intType) {
this.stringType = stringType;
this.intType = intType;
}
@Override
public String displayName() {
return "REPEAT";
}
@Override
public TOverloadResult resultType() {
return TOverloadResult.custom(new TCustomOverloadResult()
{
@Override
public TInstance resultInstance(List<TPreptimeValue> inputs, TPreptimeContext context)
{
ValueSource string = inputs.get(0).value();
int strLen;
if (string == null || string.isNull()) {
strLen = 0;
} else {
strLen = string.getString().length();
}
ValueSource length = inputs.get(1).value();
int count;
if (length == null || length.isNull() || (count = length.getInt32()) <= 0) {
return stringType.instance(0, anyContaminatingNulls(inputs));
} else {
return stringType.instance(count * strLen, anyContaminatingNulls(inputs));
}
}
});
}
@Override
protected void buildInputSets(TInputSetBuilder builder) {
builder.covers(stringType, 0).covers(intType, 1);
}
@Override
protected void doEvaluate(TExecutionContext context,
LazyList<? extends ValueSource> inputs, ValueTarget output) {
String st = inputs.get(0).getString();
if (st.isEmpty()) {
output.putString("", null);
return;
}
int count = inputs.get(1).getInt32();
if (count <= 0) {
output.putString("", null);
return;
}
output.putString(Strings.repeatString(st, count), null);
}
}