public static void mergeMapJoinUnion(UnionOperator union, GenMRProcContext ctx, int pos)
throws SemanticException {
ParseContext parseCtx = ctx.getParseCtx();
UnionProcContext uCtx = parseCtx.getUCtx();
UnionParseContext uPrsCtx = uCtx.getUnionParseContext(union);
assert uPrsCtx != null;
Task<? extends Serializable> currTask = ctx.getCurrTask();
GenMRUnionCtx uCtxTask = ctx.getUnionTask(union);
Task<? extends Serializable> uTask = null;
union.getParentOperators().get(pos);
MapredWork uPlan = null;
// union is encountered for the first time
if (uCtxTask == null) {
uCtxTask = new GenMRUnionCtx();
uPlan = GenMapRedUtils.getMapRedWork(parseCtx.getConf());
uTask = TaskFactory.get(uPlan, parseCtx.getConf());
uCtxTask.setUTask(uTask);
ctx.setUnionTask(union, uCtxTask);
} else {
uTask = uCtxTask.getUTask();
uPlan = (MapredWork) uTask.getWork();
}
// If there is a mapjoin at position 'pos'
if (uPrsCtx.getMapJoinSubq(pos)) {
GenMRMapJoinCtx mjCtx = ctx.getMapJoinCtx(ctx.getCurrMapJoinOp());
String taskTmpDir = mjCtx.getTaskTmpDir();
if (uPlan.getPathToAliases().get(taskTmpDir) == null) {
uPlan.getPathToAliases().put(taskTmpDir, new ArrayList<String>());
uPlan.getPathToAliases().get(taskTmpDir).add(taskTmpDir);
uPlan.getPathToPartitionInfo().put(taskTmpDir, new PartitionDesc(mjCtx.getTTDesc(), null));
uPlan.getAliasToWork().put(taskTmpDir, mjCtx.getRootMapJoinOp());
}
for (Task t : currTask.getParentTasks()) {
t.addDependentTask(uTask);
}
try {
boolean notDone = true;
while (notDone) {
for (Task t : currTask.getParentTasks()) {
t.removeDependentTask(currTask);
}
notDone = false;
}
} catch (ConcurrentModificationException e) {
}
} else {
setTaskPlan(ctx.getCurrAliasId(), ctx.getCurrTopOp(), uPlan, false, ctx);
}
ctx.setCurrTask(uTask);
ctx.setCurrAliasId(null);
ctx.setCurrTopOp(null);
ctx.setCurrMapJoinOp(null);
ctx.getMapCurrCtx().put(union, new GenMapRedCtx(ctx.getCurrTask(), null, null));
}
