CombineFileSplit (Hadoop 1.2.2-SNAPSHOT API)

java.lang.Object
- org.apache.hadoop.mapred.lib.CombineFileSplit

所有已实现的接口:

Writable, InputSplit

直接已知子类:

MultiFileSplit
```
public class CombineFileSplit
extends Object
implements InputSplit
```
A sub-collection of input files. Unlike FileSplit, CombineFileSplit * class does not represent a split of a file, but a split of input files into smaller sets. A split may contain blocks from different file but all the blocks in the same split are probably local to some rack
CombineFileSplit can be used to implement RecordReader's, with reading one record per file.

另请参阅:
FileSplit, CombineFileInputFormat

构造器概要

构造器
构造器和说明
`CombineFileSplit()` default constructor
`CombineFileSplit(CombineFileSplit old)` Copy constructor
`CombineFileSplit(JobConf job, Path[] files, long[] lengths)`
`CombineFileSplit(JobConf job, Path[] files, long[] start, long[] lengths, String[] locations)`

方法概要

方法
限定符和类型	方法和说明
`JobConf`	`getJob()`
`long`	`getLength()` Get the total number of bytes in the data of the `InputSplit`.
`long`	`getLength(int i)` Returns the length of the i^th Path
`long[]`	`getLengths()` Returns an array containing the lengths of the files in the split
`String[]`	`getLocations()` Returns all the Paths where this input-split resides
`int`	`getNumPaths()` Returns the number of Paths in the split
`long`	`getOffset(int i)` Returns the start offset of the i^th Path
`Path`	`getPath(int i)` Returns the i^th Path
`Path[]`	`getPaths()` Returns all the Paths in the split
`long[]`	`getStartOffsets()` Returns an array containing the startoffsets of the files in the split
`void`	`readFields(DataInput in)` Deserialize the fields of this object from `in`.
`String`	`toString()`
`void`	`write(DataOutput out)` Serialize the fields of this object to `out`.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- 构造器详细资料
  - CombineFileSplit
```
public CombineFileSplit()
```
    default constructor
  - CombineFileSplit
```
public CombineFileSplit(JobConf job,
                Path[] files,
                long[] start,
                long[] lengths,
                String[] locations)
```
  - CombineFileSplit
```
public CombineFileSplit(JobConf job,
                Path[] files,
                long[] lengths)
```
  - CombineFileSplit
```
public CombineFileSplit(CombineFileSplit old)
                 throws IOException
```
    Copy constructor
    
    抛出:
    
    IOException
- 方法详细资料
  - getJob
```
public JobConf getJob()
```
  - getLength
```
public long getLength()
```
    从接口复制的说明: InputSplit
    
    Get the total number of bytes in the data of the InputSplit.
    
    指定者:
    
    getLength 在接口中 InputSplit
    
    返回:
    the number of bytes in the input split.
  - getStartOffsets
```
public long[] getStartOffsets()
```
    Returns an array containing the startoffsets of the files in the split
  - getLengths
```
public long[] getLengths()
```
    Returns an array containing the lengths of the files in the split
  - getOffset
```
public long getOffset(int i)
```
    Returns the start offset of the i^th Path
  - getLength
```
public long getLength(int i)
```
    Returns the length of the i^th Path
  - getNumPaths
```
public int getNumPaths()
```
    Returns the number of Paths in the split
  - getPath
```
public Path getPath(int i)
```
    Returns the i^th Path
  - getPaths
```
public Path[] getPaths()
```
    Returns all the Paths in the split
  - getLocations
```
public String[] getLocations()
                      throws IOException
```
    Returns all the Paths where this input-split resides
    
    指定者:
    
    getLocations 在接口中 InputSplit
    
    返回:
    list of hostnames where data of the InputSplit is located as an array of Strings.
    
    抛出:
    
    IOException
  - readFields
```
public void readFields(DataInput in)
                throws IOException
```
    从接口复制的说明: Writable
    
    Deserialize the fields of this object from in.
    For efficiency, implementations should attempt to re-use storage in the existing object where possible.
    
    指定者:
    
    readFields 在接口中 Writable
    
    参数:
    in - DataInput to deseriablize this object from.
    
    抛出:
    
    IOException
  - write
```
public void write(DataOutput out)
           throws IOException
```
    从接口复制的说明: Writable
    
    Serialize the fields of this object to out.
    
    指定者:
    
    write 在接口中 Writable
    
    参数:
    out - DataOuput to serialize this object into.
    
    抛出:
    
    IOException
  - toString
```
public String toString()
```
    覆盖:
    
    toString 在类中 Object

类 CombineFileSplit

构造器概要

方法概要

从类继承的方法 java.lang.Object

构造器详细资料

CombineFileSplit

CombineFileSplit

CombineFileSplit

CombineFileSplit

方法详细资料

getJob

getLength

getStartOffsets

getLengths

getOffset

getLength

getNumPaths

getPath

getPaths

getLocations

readFields

write

toString