/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hbase;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
import org.apache.hadoop.hbase.KeyValue.KVComparator;
import org.apache.hadoop.hbase.util.Bytes;
import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;
/**
* Immutable POJO class for representing a table name.
* Which is of the form:
* <table namespace>:<table qualifier>
*
* Two special namespaces:
*
* 1. hbase - system namespace, used to contain hbase internal tables
* 2. default - tables with no explicit specified namespace will
* automatically fall into this namespace.
*
* ie
*
* a) foo:bar, means namespace=foo and qualifier=bar
* b) bar, means namespace=default and qualifier=bar
* c) default:bar, means namespace=default and qualifier=bar
*
* <p>
* Internally, in this class, we cache the instances to limit the number of objects and
* make the "equals" faster. We try to minimize the number of objects created of
* the number of array copy to check if we already have an instance of this TableName. The code
* is not optimize for a new instance creation but is optimized to check for existence.
* </p>
*/
@InterfaceAudience.Public
@InterfaceStability.Evolving
public final class TableName implements Comparable<TableName> {
/** See {@link #createTableNameIfNecessary(ByteBuffer, ByteBuffer)} */
private static final Set<TableName> tableCache = new CopyOnWriteArraySet<TableName>();
/** Namespace delimiter */
//this should always be only 1 byte long
public final static char NAMESPACE_DELIM = ':';
// A non-capture group so that this can be embedded.
// regex is a bit more complicated to support nuance of tables
// in default namespace
//Allows only letters, digits and '_'
public static final String VALID_NAMESPACE_REGEX =
"(?:[a-zA-Z_0-9]+)";
//Allows only letters, digits, '_', '-' and '.'
public static final String VALID_TABLE_QUALIFIER_REGEX =
"(?:[a-zA-Z_0-9][a-zA-Z_0-9-.]*)";
//Concatenation of NAMESPACE_REGEX and TABLE_QUALIFIER_REGEX,
//with NAMESPACE_DELIM as delimiter
public static final String VALID_USER_TABLE_REGEX =
"(?:(?:(?:"+VALID_NAMESPACE_REGEX+"\\"+NAMESPACE_DELIM+")?)" +
"(?:"+VALID_TABLE_QUALIFIER_REGEX+"))";
/** The hbase:meta table's name. */
public static final TableName META_TABLE_NAME =
valueOf(NamespaceDescriptor.SYSTEM_NAMESPACE_NAME_STR, "meta");
/** The Namespace table's name. */
public static final TableName NAMESPACE_TABLE_NAME =
valueOf(NamespaceDescriptor.SYSTEM_NAMESPACE_NAME_STR, "namespace");
public static final String OLD_META_STR = ".META.";
public static final String OLD_ROOT_STR = "-ROOT-";
/**
* TableName for old -ROOT- table. It is used to read/process old WALs which have
* ROOT edits.
*/
public static final TableName OLD_ROOT_TABLE_NAME = getADummyTableName(OLD_ROOT_STR);
/**
* TableName for old .META. table. Used in testing.
*/
public static final TableName OLD_META_TABLE_NAME = getADummyTableName(OLD_META_STR);
private final byte[] name;
private final String nameAsString;
private final byte[] namespace;
private final String namespaceAsString;
private final byte[] qualifier;
private final String qualifierAsString;
private final boolean systemTable;
private final int hashCode;
/**
* Check passed byte array, "tableName", is legal user-space table name.
* @return Returns passed <code>tableName</code> param
* @throws IllegalArgumentException if passed a tableName is null or
* is made of other than 'word' characters or underscores: i.e.
* <code>[a-zA-Z_0-9.-:]</code>. The ':' is used to delimit the namespace
* from the table name and can be used for nothing else.
*
* Namespace names can only contain 'word' characters
* <code>[a-zA-Z_0-9]</code> or '_'
*
* Qualifier names can only contain 'word' characters
* <code>[a-zA-Z_0-9]</code> or '_', '.' or '-'.
* The name may not start with '.' or '-'.
*
* Valid fully qualified table names:
* foo:bar, namespace=>foo, table=>bar
* org:foo.bar, namespace=org, table=>foo.bar
*/
public static byte [] isLegalFullyQualifiedTableName(final byte[] tableName) {
if (tableName == null || tableName.length <= 0) {
throw new IllegalArgumentException("Name is null or empty");
}
int namespaceDelimIndex = com.google.common.primitives.Bytes.lastIndexOf(tableName,
(byte) NAMESPACE_DELIM);
if (namespaceDelimIndex < 0){
isLegalTableQualifierName(tableName);
} else {
isLegalNamespaceName(tableName, 0, namespaceDelimIndex);
isLegalTableQualifierName(tableName, namespaceDelimIndex + 1, tableName.length);
}
return tableName;
}
public static byte [] isLegalTableQualifierName(final byte[] qualifierName) {
isLegalTableQualifierName(qualifierName, 0, qualifierName.length, false);
return qualifierName;
}
public static byte [] isLegalTableQualifierName(final byte[] qualifierName, boolean isSnapshot) {
isLegalTableQualifierName(qualifierName, 0, qualifierName.length, isSnapshot);
return qualifierName;
}
/**
* Qualifier names can only contain 'word' characters
* <code>[a-zA-Z_0-9]</code> or '_', '.' or '-'.
* The name may not start with '.' or '-'.
*
* @param qualifierName byte array containing the qualifier name
* @param start start index
* @param end end index (exclusive)
*/
public static void isLegalTableQualifierName(final byte[] qualifierName,
int start,
int end) {
isLegalTableQualifierName(qualifierName, start, end, false);
}
public static void isLegalTableQualifierName(final byte[] qualifierName,
int start,
int end,
boolean isSnapshot) {
if(end - start < 1) {
throw new IllegalArgumentException(isSnapshot ? "Snapshot" : "Table" + " qualifier must not be empty");
}
if (qualifierName[start] == '.' || qualifierName[start] == '-') {
throw new IllegalArgumentException("Illegal first character <" + qualifierName[start] +
"> at 0. " + (isSnapshot ? "Snapshot" : "User-space table") +
" qualifiers can only start with 'alphanumeric " +
"characters': i.e. [a-zA-Z_0-9]: " +
Bytes.toString(qualifierName, start, end));
}
for (int i = start; i < end; i++) {
if (Character.isLetterOrDigit(qualifierName[i]) ||
qualifierName[i] == '_' ||
qualifierName[i] == '-' ||
qualifierName[i] == '.') {
continue;
}
throw new IllegalArgumentException("Illegal character code:" + qualifierName[i] +
", <" + (char) qualifierName[i] + "> at " + i +
". " + (isSnapshot ? "Snapshot" : "User-space table") +
" qualifiers can only contain " +
"'alphanumeric characters': i.e. [a-zA-Z_0-9-.]: " +
Bytes.toString(qualifierName, start, end));
}
}
public static void isLegalNamespaceName(byte[] namespaceName) {
isLegalNamespaceName(namespaceName, 0, namespaceName.length);
}
/**
* Valid namespace characters are [a-zA-Z_0-9]
*/
public static void isLegalNamespaceName(byte[] namespaceName, int offset, int length) {
for (int i = offset; i < length; i++) {
if (Character.isLetterOrDigit(namespaceName[i])|| namespaceName[i] == '_') {
continue;
}
throw new IllegalArgumentException("Illegal character <" + namespaceName[i] +
"> at " + i + ". Namespaces can only contain " +
"'alphanumeric characters': i.e. [a-zA-Z_0-9]: " + Bytes.toString(namespaceName,
offset, length));
}
if(offset == length)
throw new IllegalArgumentException("Illegal character <" + namespaceName[offset] +
"> at " + offset + ". Namespaces can only contain " +
"'alphanumeric characters': i.e. [a-zA-Z_0-9]: " + Bytes.toString(namespaceName,
offset, length));
}
public byte[] getName() {
return name;
}
public String getNameAsString() {
return nameAsString;
}
public byte[] getNamespace() {
return namespace;
}
public String getNamespaceAsString() {
return namespaceAsString;
}
public byte[] getQualifier() {
return qualifier;
}
public String getQualifierAsString() {
return qualifierAsString;
}
public byte[] toBytes() {
return name;
}
public boolean isSystemTable() {
return systemTable;
}
@Override
public String toString() {
return nameAsString;
}
/**
*
* @throws IllegalArgumentException See {@link #valueOf(byte[])}
*/
private TableName(ByteBuffer namespace, ByteBuffer qualifier) throws IllegalArgumentException {
this.qualifier = new byte[qualifier.remaining()];
qualifier.duplicate().get(this.qualifier);
this.qualifierAsString = Bytes.toString(this.qualifier);
if (qualifierAsString.equals(OLD_ROOT_STR)) {
throw new IllegalArgumentException(OLD_ROOT_STR + " has been deprecated.");
}
if (qualifierAsString.equals(OLD_META_STR)) {
throw new IllegalArgumentException(OLD_META_STR + " no longer exists. The table has been " +
"renamed to " + META_TABLE_NAME);
}
if (Bytes.equals(NamespaceDescriptor.DEFAULT_NAMESPACE_NAME, namespace)) {
// Using the same objects: this will make the comparison faster later
this.namespace = NamespaceDescriptor.DEFAULT_NAMESPACE_NAME;
this.namespaceAsString = NamespaceDescriptor.DEFAULT_NAMESPACE_NAME_STR;
this.systemTable = false;
// The name does not include the namespace when it's the default one.
this.nameAsString = qualifierAsString;
this.name = this.qualifier;
} else {
if (Bytes.equals(NamespaceDescriptor.SYSTEM_NAMESPACE_NAME, namespace)) {
this.namespace = NamespaceDescriptor.SYSTEM_NAMESPACE_NAME;
this.namespaceAsString = NamespaceDescriptor.SYSTEM_NAMESPACE_NAME_STR;
this.systemTable = true;
} else {
this.namespace = new byte[namespace.remaining()];
namespace.duplicate().get(this.namespace);
this.namespaceAsString = Bytes.toString(this.namespace);
this.systemTable = false;
}
this.nameAsString = namespaceAsString + NAMESPACE_DELIM + qualifierAsString;
this.name = Bytes.toBytes(nameAsString);
}
this.hashCode = nameAsString.hashCode();
isLegalNamespaceName(this.namespace);
isLegalTableQualifierName(this.qualifier);
}
/**
* This is only for the old and meta tables.
*/
private TableName(String qualifier) {
this.qualifier = Bytes.toBytes(qualifier);
this.qualifierAsString = qualifier;
this.namespace = NamespaceDescriptor.SYSTEM_NAMESPACE_NAME;
this.namespaceAsString = NamespaceDescriptor.SYSTEM_NAMESPACE_NAME_STR;
this.systemTable = true;
// WARNING: nameAsString is different than name for old meta & root!
// This is by design.
this.nameAsString = namespaceAsString + NAMESPACE_DELIM + qualifierAsString;
this.name = this.qualifier;
this.hashCode = nameAsString.hashCode();
}
/**
* Check that the object does not exist already. There are two reasons for creating the objects
* only once:
* 1) With 100K regions, the table names take ~20MB.
* 2) Equals becomes much faster as it's resolved with a reference and an int comparison.
*/
private static TableName createTableNameIfNecessary(ByteBuffer bns, ByteBuffer qns) {
for (TableName tn : tableCache) {
if (Bytes.equals(tn.getQualifier(), qns) && Bytes.equals(tn.getNamespace(), bns)) {
return tn;
}
}
TableName newTable = new TableName(bns, qns);
if (tableCache.add(newTable)) { // Adds the specified element if it is not already present
return newTable;
}
// Someone else added it. Let's find it.
for (TableName tn : tableCache) {
if (Bytes.equals(tn.getQualifier(), qns) && Bytes.equals(tn.getNamespace(), bns)) {
return tn;
}
}
// this should never happen.
throw new IllegalStateException(newTable + " was supposed to be in the cache");
}
/**
* It is used to create table names for old META, and ROOT table.
* These tables are not really legal tables. They are not added into the cache.
* @return a dummy TableName instance (with no validation) for the passed qualifier
*/
private static TableName getADummyTableName(String qualifier) {
return new TableName(qualifier);
}
public static TableName valueOf(String namespaceAsString, String qualifierAsString) {
if (namespaceAsString == null || namespaceAsString.length() < 1) {
namespaceAsString = NamespaceDescriptor.DEFAULT_NAMESPACE_NAME_STR;
}
for (TableName tn : tableCache) {
if (qualifierAsString.equals(tn.getQualifierAsString()) &&
namespaceAsString.equals(tn.getNameAsString())) {
return tn;
}
}
return createTableNameIfNecessary(
ByteBuffer.wrap(Bytes.toBytes(namespaceAsString)),
ByteBuffer.wrap(Bytes.toBytes(qualifierAsString)));
}
/**
* @throws IllegalArgumentException if fullName equals old root or old meta. Some code
* depends on this. The test is buried in the table creation to save on array comparison
* when we're creating a standard table object that will be in the cache.
*/
public static TableName valueOf(byte[] fullName) throws IllegalArgumentException{
for (TableName tn : tableCache) {
if (Arrays.equals(tn.getName(), fullName)) {
return tn;
}
}
int namespaceDelimIndex = com.google.common.primitives.Bytes.lastIndexOf(fullName,
(byte) NAMESPACE_DELIM);
if (namespaceDelimIndex < 0) {
return createTableNameIfNecessary(
ByteBuffer.wrap(NamespaceDescriptor.DEFAULT_NAMESPACE_NAME),
ByteBuffer.wrap(fullName));
} else {
return createTableNameIfNecessary(
ByteBuffer.wrap(fullName, 0, namespaceDelimIndex),
ByteBuffer.wrap(fullName, namespaceDelimIndex + 1,
fullName.length - (namespaceDelimIndex + 1)));
}
}
/**
* @throws IllegalArgumentException if fullName equals old root or old meta. Some code
* depends on this.
*/
public static TableName valueOf(String name) {
for (TableName tn : tableCache) {
if (name.equals(tn.getNameAsString())) {
return tn;
}
}
int namespaceDelimIndex = name.indexOf(NAMESPACE_DELIM);
byte[] nameB = Bytes.toBytes(name);
if (namespaceDelimIndex < 0) {
return createTableNameIfNecessary(
ByteBuffer.wrap(NamespaceDescriptor.DEFAULT_NAMESPACE_NAME),
ByteBuffer.wrap(nameB));
} else {
return createTableNameIfNecessary(
ByteBuffer.wrap(nameB, 0, namespaceDelimIndex),
ByteBuffer.wrap(nameB, namespaceDelimIndex + 1,
nameB.length - (namespaceDelimIndex + 1)));
}
}
public static TableName valueOf(byte[] namespace, byte[] qualifier) {
if (namespace == null || namespace.length < 1) {
namespace = NamespaceDescriptor.DEFAULT_NAMESPACE_NAME;
}
for (TableName tn : tableCache) {
if (Arrays.equals(tn.getQualifier(), qualifier) &&
Arrays.equals(tn.getNamespace(), namespace)) {
return tn;
}
}
return createTableNameIfNecessary(
ByteBuffer.wrap(namespace), ByteBuffer.wrap(qualifier));
}
public static TableName valueOf(ByteBuffer namespace, ByteBuffer qualifier) {
if (namespace == null || namespace.remaining() < 1) {
return createTableNameIfNecessary(
ByteBuffer.wrap(NamespaceDescriptor.DEFAULT_NAMESPACE_NAME), qualifier);
}
return createTableNameIfNecessary(namespace, qualifier);
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
TableName tableName = (TableName) o;
return o.hashCode() == hashCode && nameAsString.equals(tableName.nameAsString);
}
@Override
public int hashCode() {
return hashCode;
}
/**
* For performance reasons, the ordering is not lexicographic.
*/
@Override
public int compareTo(TableName tableName) {
if (this == tableName) return 0;
if (this.hashCode < tableName.hashCode()) {
return -1;
}
if (this.hashCode > tableName.hashCode()) {
return 1;
}
return this.nameAsString.compareTo(tableName.getNameAsString());
}
/**
* Get the appropriate row comparator for this table.
*
* @return The comparator.
*/
public KVComparator getRowComparator() {
if(TableName.META_TABLE_NAME.equals(this)) {
return KeyValue.META_COMPARATOR;
}
return KeyValue.COMPARATOR;
}
}