RelInput (Calcite Core 1.2.0-incubating API)

```
public interface RelInput
```
Context from which a relational expression can initialize itself, reading from a serialized form of the relational expression.

Methods
Modifier and Type	Method and Description
`Object`	`get(String tag)`
`List<AggregateCall>`	`getAggregateCalls(String tag)`
`ImmutableBitSet`	`getBitSet(String tag)`
`List<ImmutableBitSet>`	`getBitSetList(String tag)`
`boolean`	`getBoolean(String tag, boolean default_)`
`RelOptCluster`	`getCluster()`
`RelCollation`	`getCollation()`
`RelDistribution`	`getDistribution()`
`<E extends Enum<E>> E`	`getEnum(String tag, Class<E> enumClass)` Returns an enum value.
`RexNode`	`getExpression(String tag)` Returns an expression.
`List<RexNode>`	`getExpressionList(String tag)`
`float`	`getFloat(String tag)` Returns a `float` value.
`RelNode`	`getInput()` Returns the input relational expression.
`List<RelNode>`	`getInputs()`
`RelDataType`	`getRowType(String tag)`
`RelDataType`	`getRowType(String expressionsTag, String fieldsTag)`
`String`	`getString(String tag)` Returns a `float` value.
`RelOptTable`	`getTable(String table)`
`RelTraitSet`	`getTraitSet()`
`com.google.common.collect.ImmutableList<com.google.common.collect.ImmutableList<RexLiteral>>`	`getTuples(String tag)`

getInput
```
RelNode getInput()
```
Returns the input relational expression. Throws if there is not precisely one input.

List<ImmutableBitSet> getBitSetList(String tag)

List<AggregateCall> getAggregateCalls(String tag)

getString
```
String getString(String tag)
```
Returns a float value. Throws if wrong type.

getFloat
```
float getFloat(String tag)
```
Returns a float value. Throws if not present or wrong type.

<E extends Enum<E>> E getEnum(String tag,
                            Class<E> enumClass)

Returns an enum value. Throws if not a valid member.

List<RexNode> getExpressionList(String tag)

RelDataType getRowType(String expressionsTag,
                     String fieldsTag)

com.google.common.collect.ImmutableList<com.google.common.collect.ImmutableList<RexLiteral>> getTuples(String tag)

boolean getBoolean(String tag,
                 boolean default_)

Interface RelInput