@InterfaceAudience.Public @InterfaceStability.Evolving public enum CreateFlag extends Enum<CreateFlag>
EnumSet.of(CreateFlag.CREATE, CreateFlag.APPEND)
Use the CreateFlag as follows:
- CREATE - to create a file if it does not exist,
else throw FileAlreadyExists.
- APPEND - to append to a file if it exists,
else throw FileNotFoundException.
- OVERWRITE - to truncate a file if it exists,
else throw FileNotFoundException.
- CREATE|APPEND - to create a file if it does not exist,
else append to an existing file.
- CREATE|OVERWRITE - to create a file if it does not exist,
else overwrite an existing file.
- SYNC_BLOCK - to force closed blocks to the disk device.
In addition
Syncable.hsync()
should be called after each write,
if true synchronous behavior is required.
Following combination is not valid and will result in
HadoopIllegalArgumentException
:
- APPEND|OVERWRITE
- CREATE|APPEND|OVERWRITE
Enum Constant and Description |
---|
APPEND
Append to a file.
|
CREATE
Create a file.
|
LAZY_PERSIST
Create the block on transient storage (RAM) if available.
|
OVERWRITE
Truncate/overwrite a file.
|
SYNC_BLOCK
Force closed blocks to disk.
|
Modifier and Type | Method and Description |
---|---|
static void |
validate(EnumSet<CreateFlag> flag)
Validate the CreateFlag and throw exception if it is invalid
|
static void |
validate(Object path,
boolean pathExists,
EnumSet<CreateFlag> flag)
Validate the CreateFlag for create operation
|
static CreateFlag |
valueOf(String name)
Returns the enum constant of this type with the specified name.
|
static CreateFlag[] |
values()
Returns an array containing the constants of this enum type, in
the order they are declared.
|
public static final CreateFlag CREATE
public static final CreateFlag OVERWRITE
public static final CreateFlag APPEND
public static final CreateFlag SYNC_BLOCK
public static final CreateFlag LAZY_PERSIST
public static CreateFlag[] values()
for (CreateFlag c : CreateFlag.values()) System.out.println(c);
public static CreateFlag valueOf(String name)
name
- the name of the enum constant to be returned.IllegalArgumentException
- if this enum type has no constant
with the specified nameNullPointerException
- if the argument is nullpublic static void validate(EnumSet<CreateFlag> flag)
flag
- set of CreateFlagHadoopIllegalArgumentException
- if the CreateFlag is invalidpublic static void validate(Object path, boolean pathExists, EnumSet<CreateFlag> flag) throws IOException
path
- Object representing the path; usually String or Path
pathExists
- pass true if the path exists in the file systemflag
- set of CreateFlagIOException
- on errorHadoopIllegalArgumentException
- if the CreateFlag is invalidCopyright © 2015 Apache Software Foundation. All Rights Reserved.