Package org.apache.hadoop.hdfs.protocol

Class SystemErasureCodingPolicies

java.lang.Object

org.apache.hadoop.hdfs.protocol.SystemErasureCodingPolicies

@Private
@Stable
public final class SystemErasureCodingPolicies
extends Object

The set of built-in erasure coding policies.

Although this is a private class, EC policy IDs need to be treated like a stable interface. Adding, modifying, or removing built-in policies can cause inconsistencies with older clients.

Field Summary

Fields

Modifier and Type	Field	Description
static final byte	RS_10_4_POLICY_ID
static final byte	RS_3_2_POLICY_ID
static final byte	RS_6_3_LEGACY_POLICY_ID
static final byte	RS_6_3_POLICY_ID
static final byte	XOR_2_1_POLICY_ID

Method Summary

Modifier and Type	Method	Description
static ErasureCodingPolicy	getByID(byte id)	Get a policy by policy ID.
static ErasureCodingPolicy	getByName(String name)	Get a policy by policy name.
static List<ErasureCodingPolicy>	getPolicies()	Get system defined policies.
static ErasureCodingPolicy	getReplicationPolicy()	Get the special REPLICATION policy.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

RS_6_3_POLICY_ID

public static final byte RS_6_3_POLICY_ID

See Also:

• Constant Field Values

RS_3_2_POLICY_ID

public static final byte RS_3_2_POLICY_ID

See Also:

• Constant Field Values

RS_6_3_LEGACY_POLICY_ID

public static final byte RS_6_3_LEGACY_POLICY_ID

See Also:

• Constant Field Values

XOR_2_1_POLICY_ID

public static final byte XOR_2_1_POLICY_ID

See Also:

• Constant Field Values

RS_10_4_POLICY_ID

public static final byte RS_10_4_POLICY_ID

See Also:

• Constant Field Values

Method Details

getPolicies

public static List<ErasureCodingPolicy> getPolicies()

Get system defined policies.

Returns:

system policies

getByID

public static ErasureCodingPolicy getByID(byte id)

Get a policy by policy ID.

Returns:

ecPolicy, or null if not found

getByName

public static ErasureCodingPolicy getByName(String name)

Get a policy by policy name.

Returns:

ecPolicy, or null if not found

getReplicationPolicy

public static ErasureCodingPolicy getReplicationPolicy()

Get the special REPLICATION policy.