/**
* (C) Copyright IBM Corp. 2010, 2015
*
* Licensed 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 com.ibm.bi.dml.runtime.controlprogram;
import java.util.ArrayList;
import com.ibm.bi.dml.api.DMLScript;
import com.ibm.bi.dml.hops.Hop;
import com.ibm.bi.dml.parser.WhileStatementBlock;
import com.ibm.bi.dml.parser.Expression.ValueType;
import com.ibm.bi.dml.runtime.DMLRuntimeException;
import com.ibm.bi.dml.runtime.DMLScriptException;
import com.ibm.bi.dml.runtime.DMLUnsupportedOperationException;
import com.ibm.bi.dml.runtime.controlprogram.context.ExecutionContext;
import com.ibm.bi.dml.runtime.instructions.Instruction;
import com.ibm.bi.dml.runtime.instructions.Instruction.INSTRUCTION_TYPE;
import com.ibm.bi.dml.runtime.instructions.cp.BooleanObject;
import com.ibm.bi.dml.runtime.instructions.cp.CPInstruction;
import com.ibm.bi.dml.runtime.instructions.cp.ComputationCPInstruction;
import com.ibm.bi.dml.runtime.instructions.cp.Data;
import com.ibm.bi.dml.runtime.instructions.cp.ScalarObject;
import com.ibm.bi.dml.runtime.instructions.cp.StringObject;
import com.ibm.bi.dml.runtime.instructions.cp.VariableCPInstruction;
import com.ibm.bi.dml.runtime.instructions.cp.CPInstruction.CPINSTRUCTION_TYPE;
import com.ibm.bi.dml.yarn.DMLAppMasterUtils;
public class WhileProgramBlock extends ProgramBlock
{
private ArrayList<Instruction> _predicate;
private String _predicateResultVar;
private ArrayList <Instruction> _exitInstructions ;
private ArrayList<ProgramBlock> _childBlocks;
public WhileProgramBlock(Program prog, ArrayList<Instruction> predicate) throws DMLRuntimeException{
super(prog);
_predicate = predicate;
_predicateResultVar = findPredicateResultVar ();
_exitInstructions = new ArrayList<Instruction>();
_childBlocks = new ArrayList<ProgramBlock>();
}
public void printMe() {
LOG.debug("***** while current block predicate inst: *****");
for (Instruction cp : _predicate){
cp.printMe();
}
for (ProgramBlock pb : this._childBlocks){
pb.printMe();
}
LOG.debug("***** current block inst exit: *****");
for (Instruction i : this._exitInstructions) {
i.printMe();
}
}
public void addProgramBlock(ProgramBlock childBlock) {
_childBlocks.add(childBlock);
}
public void setExitInstructions2(ArrayList<Instruction> exitInstructions)
{ _exitInstructions = exitInstructions; }
public void setExitInstructions1(ArrayList<Instruction> predicate)
{ _predicate = predicate; }
public void addExitInstruction(Instruction inst)
{ _exitInstructions.add(inst); }
public ArrayList<Instruction> getPredicate()
{ return _predicate; }
public void setPredicate( ArrayList<Instruction> predicate )
{
_predicate = predicate;
//update result var if non-empty predicate (otherwise,
//do not overwrite varname predicate in predicateResultVar)
if( _predicate != null && !_predicate.isEmpty() )
_predicateResultVar = findPredicateResultVar();
}
public String getPredicateResultVar()
{ return _predicateResultVar; }
public void setPredicateResultVar(String resultVar)
{ _predicateResultVar = resultVar; }
public ArrayList<Instruction> getExitInstructions()
{ return _exitInstructions; }
private BooleanObject executePredicate(ExecutionContext ec)
throws DMLRuntimeException, DMLUnsupportedOperationException
{
BooleanObject result = null;
try
{
if( _predicate!=null && !_predicate.isEmpty() )
{
if( _sb!=null )
{
if( DMLScript.isActiveAM() ) //set program block specific remote memory
DMLAppMasterUtils.setupProgramBlockRemoteMaxMemory(this);
WhileStatementBlock wsb = (WhileStatementBlock)_sb;
Hop predicateOp = wsb.getPredicateHops();
boolean recompile = wsb.requiresPredicateRecompilation();
result = (BooleanObject) executePredicate(_predicate, predicateOp, recompile, ValueType.BOOLEAN, ec);
}
else
result = (BooleanObject) executePredicate(_predicate, null, false, ValueType.BOOLEAN, ec);
}
else
{
//get result var
ScalarObject scalarResult = null;
Data resultData = ec.getVariable(_predicateResultVar);
if ( resultData == null ) {
//note: resultvar is a literal (can it be of any value type other than String, hence no literal/varname conflict)
scalarResult = ec.getScalarInput(_predicateResultVar, ValueType.BOOLEAN, true);
}
else {
scalarResult = ec.getScalarInput(_predicateResultVar, ValueType.BOOLEAN, false);
}
//check for invalid type String
if (scalarResult instanceof StringObject)
throw new DMLRuntimeException(this.printBlockErrorLocation() + "\nWhile predicate variable "+ _predicateResultVar + " evaluated to string " + scalarResult + " which is not allowed for predicates in DML");
//process result
if( scalarResult instanceof BooleanObject )
result = (BooleanObject)scalarResult;
else
result = new BooleanObject( scalarResult.getBooleanValue() ); //auto casting
}
}
catch(Exception ex)
{
LOG.trace("\nWhile predicate variables: "+ ec.getVariables().toString());
throw new DMLRuntimeException(this.printBlockErrorLocation() + "Failed to evaluate the WHILE predicate.", ex);
}
//(guaranteed to be non-null, see executePredicate/getScalarInput)
return result;
}
public void execute(ExecutionContext ec) throws DMLRuntimeException, DMLUnsupportedOperationException {
BooleanObject predResult = executePredicate(ec);
//execute while loop
try
{
while(predResult.getBooleanValue())
{
//execute all child blocks
for (int i=0 ; i < _childBlocks.size() ; i++) {
ec.updateDebugState(i);
_childBlocks.get(i).execute(ec);
}
predResult = executePredicate(ec);
}
}
catch(DMLScriptException e)
{
throw e;
}
catch(Exception e)
{
LOG.trace("\nWhile predicate variables: "+ ec.getVariables().toString());
throw new DMLRuntimeException(this.printBlockErrorLocation() + "Error evaluating while program block.", e);
}
//execute exit instructions
try {
executeInstructions(_exitInstructions, ec);
}
catch(Exception e)
{
throw new DMLRuntimeException(this.printBlockErrorLocation() + "Error executing while exit instructions.", e);
}
}
public ArrayList<ProgramBlock> getChildBlocks() {
return _childBlocks;
}
public void setChildBlocks(ArrayList<ProgramBlock> childs)
{
_childBlocks = childs;
}
private String findPredicateResultVar ( ) {
String result = null;
for ( Instruction si : _predicate ) {
if ( si.getType() == INSTRUCTION_TYPE.CONTROL_PROGRAM && ((CPInstruction)si).getCPInstructionType() != CPINSTRUCTION_TYPE.Variable ) {
result = ((ComputationCPInstruction) si).getOutputVariableName();
}
else if(si instanceof VariableCPInstruction && ((VariableCPInstruction)si).isVariableCastInstruction()){
result = ((VariableCPInstruction)si).getOutputVariableName();
}
}
return result;
}
public String printBlockErrorLocation(){
return "ERROR: Runtime error in while program block generated from while statement block between lines " + _beginLine + " and " + _endLine + " -- ";
}
}