TableChange.ModifyColumn (Flink : 2.0-SNAPSHOT API)

java.lang.Object
- org.apache.flink.table.catalog.TableChange.ModifyColumn

All Implemented Interfaces:

TableChange

Direct Known Subclasses:

TableChange.ModifyColumnComment, TableChange.ModifyColumnName, TableChange.ModifyColumnPosition, TableChange.ModifyPhysicalColumnType

Enclosing interface:

TableChange
```
@PublicEvolving
public static class TableChange.ModifyColumn
extends Object
implements TableChange
```
A base schema change to modify a column. The modification includes:
- change column data type
- reorder column position
- modify column comment
- rename column name
- change the computed expression
- change the metadata column expression
Some fine-grained column changes are defined in the TableChange.ModifyPhysicalColumnType, TableChange.ModifyColumnComment, TableChange.ModifyColumnPosition and TableChange.ModifyColumnName.
It is equal to the following statement:
```
    ALTER TABLE <table_name> MODIFY <column_definition> COMMENT '<column_comment>' <column_position>
 
```

Field Summary

Fields
Modifier and Type Field Description

protected Column newColumn

protected TableChange.ColumnPosition newPosition

protected Column oldColumn

Constructor Summary

Constructors
Constructor Description

ModifyColumn(Column oldColumn, Column newColumn, TableChange.ColumnPosition newPosition)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`equals(Object o)`
`Column`	`getNewColumn()`	Returns the modified `Column` instance.
`TableChange.ColumnPosition`	`getNewPosition()`	Returns the position of the modified `Column` instance.
`Column`	`getOldColumn()`	Returns the original `Column` instance.
`int`	`hashCode()`
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - oldColumn
```
protected final Column oldColumn
```
  - newColumn
```
protected final Column newColumn
```
  - newPosition
```
@Nullable
protected final TableChange.ColumnPosition newPosition
```
- Constructor Detail
  - ModifyColumn
```
public ModifyColumn(Column oldColumn,
                    Column newColumn,
                    @Nullable
                    TableChange.ColumnPosition newPosition)
```
- Method Detail
  - getOldColumn
```
public Column getOldColumn()
```
    Returns the original Column instance.
  - getNewColumn
```
public Column getNewColumn()
```
    Returns the modified Column instance.
  - getNewPosition
```
@Nullable
public TableChange.ColumnPosition getNewPosition()
```
    Returns the position of the modified Column instance. When the return value is null, it means modify the column at the original position. When the return value is FIRST, it means move the modified column to the first. When the return value is AFTER, it means move the column after the referred column.
  - equals
```
public boolean equals(Object o)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object