/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.cassandra.cql3.functions;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import org.apache.cassandra.cql3.*;
import org.apache.cassandra.db.marshal.AbstractType;
import org.apache.cassandra.db.marshal.CollectionType;
import org.apache.cassandra.db.marshal.ListType;
import org.apache.cassandra.db.marshal.MapType;
import org.apache.cassandra.db.marshal.SetType;
import org.apache.cassandra.exceptions.InvalidRequestException;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.cassandra.serializers.MarshalException;
public class FunctionCall extends Term.NonTerminal
{
private final Function fun;
private final List<Term> terms;
private FunctionCall(Function fun, List<Term> terms)
{
this.fun = fun;
this.terms = terms;
}
public void collectMarkerSpecification(VariableSpecifications boundNames)
{
for (Term t : terms)
t.collectMarkerSpecification(boundNames);
}
public Term.Terminal bind(List<ByteBuffer> values) throws InvalidRequestException
{
return makeTerminal(fun, bindAndGet(values));
}
public ByteBuffer bindAndGet(List<ByteBuffer> values) throws InvalidRequestException
{
List<ByteBuffer> buffers = new ArrayList<ByteBuffer>(terms.size());
for (Term t : terms)
{
// For now, we don't allow nulls as argument as no existing function needs it and it
// simplify things.
ByteBuffer val = t.bindAndGet(values);
if (val == null)
throw new InvalidRequestException(String.format("Invalid null value for argument to %s", fun));
buffers.add(val);
}
return executeInternal(fun, buffers);
}
private static ByteBuffer executeInternal(Function fun, List<ByteBuffer> params) throws InvalidRequestException
{
ByteBuffer result = fun.execute(params);
try
{
// Check the method didn't lied on it's declared return type
if (result != null)
fun.returnType().validate(result);
return result;
}
catch (MarshalException e)
{
throw new RuntimeException(String.format("Return of function %s (%s) is not a valid value for its declared return type %s",
fun, ByteBufferUtil.bytesToHex(result), fun.returnType().asCQL3Type()));
}
}
public boolean containsBindMarker()
{
for (Term t : terms)
{
if (t.containsBindMarker())
return true;
}
return false;
}
private static Term.Terminal makeTerminal(Function fun, ByteBuffer result) throws InvalidRequestException
{
if (!(fun.returnType() instanceof CollectionType))
return new Constants.Value(result);
switch (((CollectionType)fun.returnType()).kind)
{
case LIST: return Lists.Value.fromSerialized(result, (ListType)fun.returnType());
case SET: return Sets.Value.fromSerialized(result, (SetType)fun.returnType());
case MAP: return Maps.Value.fromSerialized(result, (MapType)fun.returnType());
}
throw new AssertionError();
}
public static class Raw implements Term.Raw
{
private final String functionName;
private final List<Term.Raw> terms;
public Raw(String functionName, List<Term.Raw> terms)
{
this.functionName = functionName;
this.terms = terms;
}
public Term prepare(ColumnSpecification receiver) throws InvalidRequestException
{
Function fun = Functions.get(functionName, terms, receiver);
List<Term> parameters = new ArrayList<Term>(terms.size());
boolean allTerminal = true;
for (int i = 0; i < terms.size(); i++)
{
Term t = terms.get(i).prepare(Functions.makeArgSpec(receiver, fun, i));
if (t instanceof NonTerminal)
allTerminal = false;
parameters.add(t);
}
// If all parameters are terminal and the function is pure, we can
// evaluate it now, otherwise we'd have to wait execution time
return allTerminal && fun.isPure()
? makeTerminal(fun, execute(fun, parameters))
: new FunctionCall(fun, parameters);
}
// All parameters must be terminal
private static ByteBuffer execute(Function fun, List<Term> parameters) throws InvalidRequestException
{
List<ByteBuffer> buffers = new ArrayList<ByteBuffer>(parameters.size());
for (Term t : parameters)
{
assert t instanceof Term.Terminal;
buffers.add(((Term.Terminal)t).get());
}
return executeInternal(fun, buffers);
}
public boolean isAssignableTo(ColumnSpecification receiver)
{
AbstractType<?> returnType = Functions.getReturnType(functionName, receiver.ksName, receiver.cfName);
// Note: if returnType == null, it means the function doesn't exist. We may get this if an undefined function
// is used as argument of another, existing, function. In that case, we return true here because we'll catch
// the fact that the method is undefined latter anyway and with a more helpful error message that if we were
// to return false here.
return returnType == null || receiver.type.isValueCompatibleWith(returnType);
}
@Override
public String toString()
{
StringBuilder sb = new StringBuilder();
sb.append(functionName).append("(");
for (int i = 0; i < terms.size(); i++)
{
if (i > 0) sb.append(", ");
sb.append(terms.get(i));
}
return sb.append(")").toString();
}
}
}