Tuple (ODPS SDK Commons for Mapreduce/Graph 0.45.2-public API)

java.lang.Object
- com.aliyun.odps.io.Tuple

All Implemented Interfaces:

Writable, WritableComparable<Object>, Comparable<Object>
```
public class Tuple
extends Object
implements WritableComparable<Object>
```
Tuple 是 Writable 对象的有序集.
Tuple 将 Writable 对象保存在一个 List 中，每个 Writable 对象都是一个 Tuple域（Field）。
Tuple 的方法与 Record 有些类似，不同之处：
- Tuple 不含 schema 信息，只是数据的集合。
- Tuple 可以随意创建，Record 由 MapReduce 框架创建。
See Also:

TupleReaderWriter

Field Summary

Fields
Modifier and Type	Field and Description
`static char`	`DELIM` `toDelimitedString()` 使用的默认列分隔符：CTRL + A
`static String`	`NULLINDICATOR` `toDelimitedString()` 使用的默认NULL指示符: \N

Constructor Summary

Constructors
Constructor and Description
`Tuple()` 默认构造函数
`Tuple(int size)` 构造一个指定大小的 Tuple.
`Tuple(List<Writable> vals, boolean reference)` 给定 `List` 构造 Tuple.
`Tuple(Tuple tuple, boolean reference)` 复制另一个 Tuple 的数据
`Tuple(Writable[] fields)` 给定 `Writable` 数组构造 Tuple.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`append(Collection<Writable> vals)` 将集合中的field添加到Tuple
`void`	`append(Writable val)` Append a field to a tuple.
`void`	`append(Writable[] vals)` 将数组中的field添加到Tuple
`void`	`clear()` 清空Tuple中的所有field
`Tuple`	`clone()` 生成当前Tuple的拷贝
`int`	`compareTo(Object other)` 比较两个Tuple对象，依次比较Tuple中的各个field
`boolean`	`equals(Object other)` 比较两个Tuple对象是否相等
`Writable`	`get(int fieldNum)` Get the value in a given field.
`List<Writable>`	`getAll()` Get all of the fields in the tuple as a list.
`int`	`hashCode()` 获取Tuple对象的hash直
`void`	`readFields(DataInput in)` 从指定的输入流中反序列化出Tuple对象
`void`	`set(int fieldNum, Writable val)` Set the value in a given field.
`void`	`set(List<Writable> vals)` 设置Tuple中存放的`Writable`对象，复用vals
`void`	`set(Writable[] vals)` 设置Tuple中存放的`Writable`对象
`int`	`size()` Find the size of the tuple.
`Writable[]`	`toArray()` 得到Tuple的数组形式
`String`	`toDelimitedString()` 将Tuple中的所有field使用`DELIM`连接起来，field为null时使用`NULLINDICATOR`代替.
`String`	`toDelimitedString(char delim)` 将Tuple中的所有field使用指定的delim连接起来，field为null时使用`NULLINDICATOR`代替.
`String`	`toDelimitedString(char delim, String nullIndicator)` 将Tuple中的所有field使用指定的delim连接起来，field为null时使用指定的nullIndicator代替.
`String`	`toString()` 获取Tuple的字符串表示形式
`void`	`write(DataOutput out)` 将Tuple对象序列化至指定的输出流中

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

- Field Detail
  - DELIM
```
public static final char DELIM
```
    toDelimitedString() 使用的默认列分隔符：CTRL + A
    
    See Also:
    
    Constant Field Values
  - NULLINDICATOR
```
public static final String NULLINDICATOR
```
    toDelimitedString() 使用的默认NULL指示符: \N
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - Tuple
```
public Tuple()
```
    默认构造函数
  - Tuple
```
public Tuple(int size)
```
    构造一个指定大小的 Tuple.
    
    Parameters:
    
    size - Writable 对象个数
  - Tuple
```
public Tuple(Writable[] fields)
```
    给定 Writable 数组构造 Tuple.
    
    Parameters:
    
    fields - Writable 数组
  - Tuple
```
public Tuple(List<Writable> vals,
             boolean reference)
```
    给定 List 构造 Tuple.
    
    Parameters:
    
    vals -
    
    reference - 如果为true，新创建的 Tuple 直接使用 vals 保存 Fields，否则，会创建一个新的 List.
  - Tuple
```
public Tuple(Tuple tuple,
             boolean reference)
```
    复制另一个 Tuple 的数据
    
    Parameters:
    
    tuple - 待复制的 Tuple 对象
    
    reference - 如果为true，共享 List.
- Method Detail
  - size
```
public int size()
```
    Find the size of the tuple. Used to be called arity().
    
    Returns:
    
    number of fields in the tuple.
  - get
```
public Writable get(int fieldNum)
```
    Get the value in a given field.
    
    Parameters:
    
    fieldNum - Number of the field to get the value for.
    
    Returns:
    
    value, as an Object.
    
    Throws:
    
    IOException - if the field number is greater than or equal to the number of fields in the tuple.
  - getAll
```
public List<Writable> getAll()
```
    Get all of the fields in the tuple as a list.
    
    Returns:
    
    List<Object> containing the fields of the tuple in order.
  - toArray
```
public Writable[] toArray()
```
    得到Tuple的数组形式
    
    Returns:
    
    返回Tuple中存放的Writable数组
  - set
```
public void set(int fieldNum,
                Writable val)
         throws IOException
```
    Set the value in a given field.
    
    Parameters:
    
    fieldNum - Number of the field to set the value for.
    
    val - Writable to put in the indicated field.
    
    Throws:
    
    IOException - if the field number is greater than or equal to the number of fields in the tuple.
  - set
```
public void set(List<Writable> vals)
```
    设置Tuple中存放的Writable对象，复用vals
    
    Parameters:
    
    vals - 待设置的Writable对象
  - set
```
public void set(Writable[] vals)
```
    设置Tuple中存放的Writable对象
    
    Parameters:
    
    vals - 待设置的Writable对象
  - append
```
public void append(Writable val)
```
    Append a field to a tuple. This method is not efficient as it may force copying of existing data in order to grow the data structure. Whenever possible you should construct your Tuple with the Tuple(int) method and then fill in the values with set(), rather than construct it with Tuple() and append values.
    
    Parameters:
    
    val - Object to append to the tuple.
  - append
```
public void append(Writable[] vals)
```
    将数组中的field添加到Tuple
    
    Parameters:
    
    vals - 待添加的field
  - append
```
public void append(Collection<Writable> vals)
```
    将集合中的field添加到Tuple
    
    Parameters:
    
    vals - 待添加的field
  - clear
```
public void clear()
```
    清空Tuple中的所有field
  - toDelimitedString
```
public String toDelimitedString()
```
    将Tuple中的所有field使用DELIM连接起来，field为null时使用NULLINDICATOR代替.
    
    Returns:
    
    连接后的字符串
  - toDelimitedString
```
public String toDelimitedString(char delim)
```
    将Tuple中的所有field使用指定的delim连接起来，field为null时使用NULLINDICATOR代替.
    
    Parameters:
    
    delim - 指定的分割符
    
    Returns:
    
    连接后的字符串
  - toDelimitedString
```
public String toDelimitedString(char delim,
                                String nullIndicator)
```
    将Tuple中的所有field使用指定的delim连接起来，field为null时使用指定的nullIndicator代替.
    
    Parameters:
    
    delim - 指定的分割符
    
    nullIndicator - 指定的null替代字符串
    
    Returns:
    
    连接后的字符串
  - toString
```
public String toString()
```
    获取Tuple的字符串表示形式
    
    Overrides:
    
    toString in class Object
  - compareTo
```
public int compareTo(Object other)
```
    比较两个Tuple对象，依次比较Tuple中的各个field
    
    Specified by:
    
    compareTo in interface Comparable<Object>
  - equals
```
public boolean equals(Object other)
```
    比较两个Tuple对象是否相等
    
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    获取Tuple对象的hash直
    
    Overrides:
    
    hashCode in class Object
  - write
```
public void write(DataOutput out)
           throws IOException
```
    将Tuple对象序列化至指定的输出流中
    
    Specified by:
    
    write in interface Writable
    
    Throws:
    
    IOException
  - readFields
```
public void readFields(DataInput in)
                throws IOException
```
    从指定的输入流中反序列化出Tuple对象
    
    Specified by:
    
    readFields in interface Writable
    
    Throws:
    
    IOException
  - clone
```
public Tuple clone()
```
    生成当前Tuple的拷贝
    
    Overrides:
    
    clone in class Object

Class Tuple

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DELIM

NULLINDICATOR

Constructor Detail

Tuple

Tuple

Tuple

Tuple

Tuple

Method Detail

size

get

getAll

toArray

set

set

set

append

append

append

clear

toDelimitedString

toDelimitedString

toDelimitedString

toString

compareTo

equals

hashCode

write

readFields

clone