DistCpOptionSwitch (Hadoop 1.2.2-SNAPSHOT API)

java.lang.Object
- java.lang.Enum<DistCpOptionSwitch>
- - org.apache.hadoop.tools.distcp2.DistCpOptionSwitch

所有已实现的接口:

Serializable, Comparable<DistCpOptionSwitch>
```
public enum DistCpOptionSwitch
extends Enum<DistCpOptionSwitch>
```
Enumeration mapping configuration keys to distcp command line options.

枚举常量概要

枚举常量
枚举常量和说明
`ATOMIC_COMMIT` Copy all the source files and commit them atomically to the target This is typically useful in cases where there is a process polling for availability of a file/dir.
`BANDWIDTH` Specify bandwidth per map in MB
`BLOCKING` Should DisctpExecution be blocking
`COPY_STRATEGY` Copy strategy is use.
`DELETE_MISSING` Deletes missing files in target that are missing from source This allows the target to be in sync with the source contents Typically used in conjunction with SYNC_FOLDERS Incompatible with ATOMIC_COMMIT
`FILE_LIMIT`
`IGNORE_FAILURES` Ignores any failures during copy, and continues with rest.
`LOG_PATH` Log path where distcp output logs are written to
`MAX_MAPS` Max number of maps to use during copy.
`OVERWRITE` Overwrite target-files unconditionally.
`PRESERVE_STATUS` Preserves status of file/path in the target.
`SIZE_LIMIT`
`SKIP_CRC` Skip CRC checks between source and target, when determining what files need to be copied.
`SOURCE_FILE_LISTING` Source file listing can be provided to DistCp in a file.
`SSL_CONF` Configuration file to use with hftps:// for securely copying files across clusters.
`SYNC_FOLDERS` Update target location by copying only files that are missing in the target.
`WORK_PATH` Work path to be used only in conjunction in Atomic commit

方法概要

方法
限定符和类型	方法和说明
`static void`	`addToConf(Configuration conf, DistCpOptionSwitch option)` Helper function to set an option to hadoop configuration object
`static void`	`addToConf(Configuration conf, DistCpOptionSwitch option, String value)` Helper function to add an option to hadoop configuration object
`String`	`getConfigLabel()` Get Configuration label for the option
`org.apache.commons.cli.Option`	`getOption()` Get CLI Option corresponding to the distcp option
`String`	`getSwitch()` Get Switch symbol
`String`	`toString()`
`static DistCpOptionSwitch`	`valueOf(String name)` 返回带有指定名称的该类型的枚举常量。
`static DistCpOptionSwitch[]`	`values()` 按照声明该枚举类型的常量的顺序, 返回包含这些常量的数组。

从类继承的方法 java.lang.Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, valueOf

从类继承的方法 java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

- 枚举常量详细资料
  - IGNORE_FAILURES
```
public static final DistCpOptionSwitch IGNORE_FAILURES
```
    Ignores any failures during copy, and continues with rest. Logs failures in a file
  - PRESERVE_STATUS
```
public static final DistCpOptionSwitch PRESERVE_STATUS
```
    Preserves status of file/path in the target. Default behavior with -p, is to preserve replication, block size, user, group and permission on the target file If any of the optional switches are present among rbugp, then only the corresponding file attribute is preserved
  - SYNC_FOLDERS
```
public static final DistCpOptionSwitch SYNC_FOLDERS
```
    Update target location by copying only files that are missing in the target. This can be used to periodically sync two folders across source and target. Typically used with DELETE_MISSING Incompatible with ATOMIC_COMMIT
  - DELETE_MISSING
```
public static final DistCpOptionSwitch DELETE_MISSING
```
    Deletes missing files in target that are missing from source This allows the target to be in sync with the source contents Typically used in conjunction with SYNC_FOLDERS Incompatible with ATOMIC_COMMIT
  - SSL_CONF
```
public static final DistCpOptionSwitch SSL_CONF
```
    Configuration file to use with hftps:// for securely copying files across clusters. Typically the configuration file contains truststore/keystore information such as location, password and type
  - MAX_MAPS
```
public static final DistCpOptionSwitch MAX_MAPS
```
    Max number of maps to use during copy. DistCp will split work as equally as possible among these maps
  - SOURCE_FILE_LISTING
```
public static final DistCpOptionSwitch SOURCE_FILE_LISTING
```
    Source file listing can be provided to DistCp in a file. This allows DistCp to copy random list of files from source and copy them to target
  - ATOMIC_COMMIT
```
public static final DistCpOptionSwitch ATOMIC_COMMIT
```
    Copy all the source files and commit them atomically to the target This is typically useful in cases where there is a process polling for availability of a file/dir. This option is incompatible with SYNC_FOLDERS & DELETE_MISSING
  - WORK_PATH
```
public static final DistCpOptionSwitch WORK_PATH
```
    Work path to be used only in conjunction in Atomic commit
  - LOG_PATH
```
public static final DistCpOptionSwitch LOG_PATH
```
    Log path where distcp output logs are written to
  - COPY_STRATEGY
```
public static final DistCpOptionSwitch COPY_STRATEGY
```
    Copy strategy is use. This could be dynamic or uniform size etc. DistCp would use an appropriate input format based on this.
  - SKIP_CRC
```
public static final DistCpOptionSwitch SKIP_CRC
```
    Skip CRC checks between source and target, when determining what files need to be copied.
  - OVERWRITE
```
public static final DistCpOptionSwitch OVERWRITE
```
    Overwrite target-files unconditionally.
  - BLOCKING
```
public static final DistCpOptionSwitch BLOCKING
```
    Should DisctpExecution be blocking
  - FILE_LIMIT
```
public static final DistCpOptionSwitch FILE_LIMIT
```
  - SIZE_LIMIT
```
public static final DistCpOptionSwitch SIZE_LIMIT
```
  - BANDWIDTH
```
public static final DistCpOptionSwitch BANDWIDTH
```
    Specify bandwidth per map in MB
- 方法详细资料
  - values
```
public static DistCpOptionSwitch[] values()
```
    按照声明该枚举类型的常量的顺序, 返回包含这些常量的数组。该方法可用于迭代常量, 如下所示:
```
for (DistCpOptionSwitch c : DistCpOptionSwitch.values())
    System.out.println(c);
```
  - valueOf
```
public static DistCpOptionSwitch valueOf(String name)
```
    返回带有指定名称的该类型的枚举常量。字符串必须与用于声明该类型的枚举常量的标识符完全匹配。(不允许有多余的空格字符。)
    
    参数:
    name - 要返回的枚举常量的名称。
  - getConfigLabel
```
public String getConfigLabel()
```
    Get Configuration label for the option
    
    返回:
    configuration label name
  - getOption
```
public org.apache.commons.cli.Option getOption()
```
    Get CLI Option corresponding to the distcp option
    
    返回:
    option
  - getSwitch
```
public String getSwitch()
```
    Get Switch symbol
    
    返回:
    switch symbol char
  - toString
```
public String toString()
```
    覆盖:
    
    toString 在类中 Enum<DistCpOptionSwitch>
  - addToConf
```
public static void addToConf(Configuration conf,
             DistCpOptionSwitch option,
             String value)
```
    Helper function to add an option to hadoop configuration object
    
    参数:
    conf - - Configuration object to include the option
    option - - Option to add
    value - - Value
  - addToConf
```
public static void addToConf(Configuration conf,
             DistCpOptionSwitch option)
```
    Helper function to set an option to hadoop configuration object
    
    参数:
    conf - - Configuration object to include the option
    option - - Option to add

枚举 DistCpOptionSwitch

枚举常量概要

方法概要

从类继承的方法 java.lang.Enum

从类继承的方法 java.lang.Object

枚举常量详细资料

IGNORE_FAILURES

PRESERVE_STATUS

SYNC_FOLDERS

DELETE_MISSING

SSL_CONF

MAX_MAPS

SOURCE_FILE_LISTING

ATOMIC_COMMIT

WORK_PATH

LOG_PATH

COPY_STRATEGY

SKIP_CRC

OVERWRITE

BLOCKING

FILE_LIMIT

SIZE_LIMIT

BANDWIDTH

方法详细资料

values

valueOf

getConfigLabel

getOption

getSwitch

toString

addToConf

addToConf