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/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or .
 */
package org.hibernate;

import java.io.Serializable;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Objects;
import java.util.Set;

import jakarta.persistence.PessimisticLockScope;
import org.hibernate.query.Query;
import org.hibernate.query.spi.QueryOptions;

import static java.util.Collections.emptySet;
import static java.util.Collections.unmodifiableSet;

/**
 * Contains a set of options describing how a row of a database table
 * mapped by an entity should be locked. For
 * {@link Session#lock(Object, LockOptions)},
 * {@link Session#get(Class, Object, LockOptions)}, or
 * {@link Session#refresh(Object, LockOptions)}, the relevant options
 * are:
 * 
    *
  • the {@link #getLockMode() lock mode}, *
  • the {@link #getTimeOut() pessimistic lock timeout}, and *
  • the {@link #getLockScope() lock scope}, that is, whether the * lock extends to rows of owned collections. *
*

* Timeout and lock scope are ignored if the specified {@code LockMode} * represents a flavor of {@linkplain LockMode#OPTIMISTIC optimistic} * locking. *

* In HQL and criteria queries, lock modes can be defined in an even * more granular fashion, with the option to specify a lock mode that * {@linkplain #setAliasSpecificLockMode(String, LockMode) applies * only to a certain query alias}. *

* Finally, the use of follow-on locking may be force enabled or disabled, * overriding the {@linkplain org.hibernate.dialect.Dialect#useFollowOnLocking * default behavior of the SQL dialect} by passing a non-null argument * to {@link #setFollowOnLocking(Boolean)}. * * @author Scott Marlow */ public class LockOptions implements Serializable { /** * Represents {@link LockMode#NONE}, to which timeout and scope are * not applicable. */ public static final LockOptions NONE = new LockOptions( true, LockMode.NONE ); /** * Represents {@link LockMode#READ}, to which timeout and scope are * not applicable. */ public static final LockOptions READ = new LockOptions( true, LockMode.READ ); /** * Represents {@link LockMode#OPTIMISTIC}. */ static final LockOptions OPTIMISTIC = new LockOptions( true, LockMode.OPTIMISTIC ); /** * Represents {@link LockMode#OPTIMISTIC_FORCE_INCREMENT}, to which * timeout and scope are not applicable. */ static final LockOptions OPTIMISTIC_FORCE_INCREMENT = new LockOptions( true, LockMode.OPTIMISTIC_FORCE_INCREMENT ); /** * Represents {@link LockMode#PESSIMISTIC_READ}. */ static final LockOptions PESSIMISTIC_READ = new LockOptions( true, LockMode.PESSIMISTIC_READ ); /** * Represents {@link LockMode#PESSIMISTIC_WRITE}. */ static final LockOptions PESSIMISTIC_WRITE = new LockOptions( true, LockMode.PESSIMISTIC_WRITE ); /** * Represents {@link LockMode#PESSIMISTIC_FORCE_INCREMENT}. */ static final LockOptions PESSIMISTIC_FORCE_INCREMENT = new LockOptions( true, LockMode.PESSIMISTIC_FORCE_INCREMENT ); /** * Represents {@link LockMode#UPGRADE_NOWAIT}. */ static final LockOptions UPGRADE_NOWAIT = new LockOptions( true, LockMode.UPGRADE_NOWAIT ); /** * Represents {@link LockMode#UPGRADE_SKIPLOCKED}. */ static final LockOptions UPGRADE_SKIPLOCKED = new LockOptions( true, LockMode.UPGRADE_SKIPLOCKED ); /** * Represents {@link LockMode#PESSIMISTIC_WRITE} with * {@linkplain #WAIT_FOREVER no timeout}, and * {@linkplain PessimisticLockScope#NORMAL no extension of the * lock to owned collections}. */ public static final LockOptions UPGRADE = PESSIMISTIC_WRITE; /** * Indicates that the database should not wait at all to acquire * a pessimistic lock which is not immediately available. This * has the same effect as {@link LockMode#UPGRADE_NOWAIT}. * * @see #getTimeOut */ public static final int NO_WAIT = 0; /** * Indicates that there is no timeout for the lock acquisition, * that is, that the database should in principle wait forever * to obtain the lock. * * @see #getTimeOut */ public static final int WAIT_FOREVER = -1; /** * Indicates that rows which are already locked should be skipped. * * @see #getTimeOut() * @deprecated use {@link LockMode#UPGRADE_SKIPLOCKED} */ @Deprecated public static final int SKIP_LOCKED = -2; private final boolean immutable; private LockMode lockMode; private int timeout; private boolean scope; private Boolean followOnLocking; private Map aliasSpecificLockModes; /** * Construct an instance with mode {@link LockMode#NONE} and * timeout {@link #WAIT_FOREVER}. */ public LockOptions() { immutable = false; lockMode = LockMode.NONE; timeout = WAIT_FOREVER; } /** * Construct an instance with the given {@linkplain LockMode mode} * and {@link #WAIT_FOREVER}. * * @param lockMode The initial lock mode */ public LockOptions(LockMode lockMode) { immutable = false; this.lockMode = lockMode; timeout = WAIT_FOREVER; } /** * Construct an instance with the given {@linkplain LockMode mode} * and timeout. * * @param lockMode The initial lock mode * @param timeout The initial timeout */ public LockOptions(LockMode lockMode, int timeout) { immutable = false; this.lockMode = lockMode; this.timeout = timeout; } /** * Construct an instance with the given {@linkplain LockMode mode}, * timeout, and {@link PessimisticLockScope scope}. * * @param lockMode The initial lock mode * @param timeout The initial timeout * @param scope The initial lock scope */ public LockOptions(LockMode lockMode, int timeout, PessimisticLockScope scope) { immutable = false; this.lockMode = lockMode; this.timeout = timeout; this.scope = scope == PessimisticLockScope.EXTENDED; } /** * Internal operation used to create immutable global instances. */ private LockOptions(boolean immutable, LockMode lockMode) { this.immutable = immutable; this.lockMode = lockMode; timeout = WAIT_FOREVER; } /** * Determine of the lock options are empty. * * @return {@code true} if the lock options are equivalent to * {@link LockOptions#NONE}. */ public boolean isEmpty() { return lockMode == LockMode.NONE && timeout == WAIT_FOREVER && followOnLocking == null && !scope && !hasAliasSpecificLockModes(); } /** * Retrieve the overall lock mode in effect for this set of options. * * @return the overall lock mode */ public LockMode getLockMode() { return lockMode; } /** * Set the overall {@linkplain LockMode lock mode}. The default is * {@link LockMode#NONE}, that is, no locking at all. * * @param lockMode the new overall lock mode * @return {@code this} for method chaining */ public LockOptions setLockMode(LockMode lockMode) { if ( immutable ) { throw new UnsupportedOperationException("immutable global instance of LockMode"); } this.lockMode = lockMode; return this; } /** * Specify the {@link LockMode} to be used for the given query alias. * * @param alias the query alias to which the lock mode applies * @param lockMode the lock mode to apply to the given alias * @return {@code this} for method chaining * * @see Query#setLockMode(String, LockMode) */ public LockOptions setAliasSpecificLockMode(String alias, LockMode lockMode) { if ( immutable ) { throw new UnsupportedOperationException("immutable global instance of LockMode"); } if ( aliasSpecificLockModes == null ) { aliasSpecificLockModes = new LinkedHashMap<>(); } if ( lockMode == null ) { aliasSpecificLockModes.remove( alias ); } else { aliasSpecificLockModes.put( alias, lockMode ); } return this; } /** * Get the {@link LockMode} explicitly specified for the given alias * via {@link #setAliasSpecificLockMode(String, LockMode)}. *

* Differs from {@link #getEffectiveLockMode(String)} in that here we * only return an explicitly specified alias-specific lock mode. * * @param alias The alias for which to locate the explicit lock mode. * @return The explicit lock mode for that alias. */ public LockMode getAliasSpecificLockMode(String alias) { return aliasSpecificLockModes == null ? null : aliasSpecificLockModes.get( alias ); } /** * Determine the {@link LockMode} to apply to the given alias. If no * mode was {@linkplain #setAliasSpecificLockMode(String, LockMode)} * explicitly set}, the {@linkplain #getLockMode()} overall mode} is * returned. If the overall lock mode is also {@code null}, * {@link LockMode#NONE} is returned. *

* Differs from {@link #getAliasSpecificLockMode(String)} in that here * we fall back to only returning the overall lock mode. * * @param alias The alias for which to locate the effective lock mode. * @return The effective lock mode. */ public LockMode getEffectiveLockMode(String alias) { LockMode lockMode = getAliasSpecificLockMode( alias ); if ( lockMode == null ) { lockMode = this.lockMode; } return lockMode == null ? LockMode.NONE : lockMode; } /** * Does this {@code LockOptions} instance define alias-specific lock * modes? * * @return {@code true} if this object defines alias-specific lock modes; * {@code false} otherwise. */ public boolean hasAliasSpecificLockModes() { return aliasSpecificLockModes != null && !aliasSpecificLockModes.isEmpty(); } /** * The number of aliases that have alias-specific lock modes specified. * * @return the number of explicitly defined alias lock modes. */ public int getAliasLockCount() { return aliasSpecificLockModes == null ? 0 : aliasSpecificLockModes.size(); } /** * Iterator over {@link Map.Entry}s, each containing an alias and its * {@link LockMode}. * * @return an iterator over the {@link Map.Entry}s * @deprecated use {@link #getAliasSpecificLocks()} */ @Deprecated public Iterator> getAliasLockIterator() { return getAliasSpecificLocks().iterator(); } /** * Set of {@link Map.Entry}s, each associating an alias with its * specified {@linkplain #setAliasSpecificLockMode alias-specific} * {@link LockMode}. * * @return an iterable with the {@link Map.Entry}s */ public Set> getAliasSpecificLocks() { return aliasSpecificLockModes == null ? emptySet() : unmodifiableSet( aliasSpecificLockModes.entrySet() ); } /** * Currently needed for follow-on locking. * * @return The greatest of all requested lock modes. */ public LockMode findGreatestLockMode() { LockMode lockModeToUse = getLockMode(); if ( lockModeToUse == null ) { lockModeToUse = LockMode.NONE; } if ( aliasSpecificLockModes == null ) { return lockModeToUse; } for ( LockMode lockMode : aliasSpecificLockModes.values() ) { if ( lockMode.greaterThan( lockModeToUse ) ) { lockModeToUse = lockMode; } } return lockModeToUse; } /** * The current timeout, a maximum amount of time in milliseconds * that the database should wait to obtain a pessimistic lock before * returning an error to the client. *

* {@link #NO_WAIT}, {@link #WAIT_FOREVER}, or {@link #SKIP_LOCKED} * represent 3 "magic" values. * * @return a timeout in milliseconds, {@link #NO_WAIT}, * {@link #WAIT_FOREVER}, or {@link #SKIP_LOCKED} */ public int getTimeOut() { return timeout; } /** * Set the timeout, that is, the maximum amount of time in milliseconds * that the database should wait to obtain a pessimistic lock before * returning an error to the client. *

* {@link #NO_WAIT}, {@link #WAIT_FOREVER}, or {@link #SKIP_LOCKED} * represent 3 "magic" values. * * @param timeout the new timeout setting, in milliseconds * @return {@code this} for method chaining * * @see #getTimeOut */ public LockOptions setTimeOut(int timeout) { if ( immutable ) { throw new UnsupportedOperationException("immutable global instance of LockMode"); } this.timeout = timeout; return this; } /** * The current lock scope: *

    *
  • {@link PessimisticLockScope#EXTENDED} means the lock * extends to rows of owned collections, but *
  • {@link PessimisticLockScope#NORMAL} means only the entity * table and secondary tables are locked. *
* * @return the current {@link PessimisticLockScope} */ public PessimisticLockScope getLockScope() { return scope ? PessimisticLockScope.EXTENDED : PessimisticLockScope.NORMAL; } /** * Set the lock scope: *
    *
  • {@link PessimisticLockScope#EXTENDED} means the lock * extends to rows of owned collections, but *
  • {@link PessimisticLockScope#NORMAL} means only the entity * table and secondary tables are locked. *
* * @param scope the new {@link PessimisticLockScope} * @return {@code this} for method chaining */ public LockOptions setLockScope(PessimisticLockScope scope) { if ( immutable ) { throw new UnsupportedOperationException("immutable global instance of LockMode"); } return setScope(scope==PessimisticLockScope.EXTENDED); } /** * The current lock scope setting: *
    *
  • {@code true} means the lock extends to rows of owned * collections, but *
  • {@code false} means only the entity table and secondary * tables are locked. *
* * @return {@code true} if the lock extends to owned associations * * @deprecated use {@link #getLockScope()} */ @Deprecated(since = "6.2") public boolean getScope() { return scope; } /** * Set the lock scope setting: *
    *
  • {@code true} means the lock extends to rows of owned * collections, but *
  • {@code false} means only the entity table and secondary * tables are locked. *
* * @param scope the new scope setting * @return {@code this} for method chaining * * @deprecated use {@link #setLockScope(PessimisticLockScope)} */ @Deprecated(since = "6.2") public LockOptions setScope(boolean scope) { if ( immutable ) { throw new UnsupportedOperationException("immutable global instance of LockMode"); } this.scope = scope; return this; } /** * Returns a value indicating if follow-on locking was force * enabled or disabled, overriding the default behavior of * the SQL dialect. * * @return {@code true} if follow-on locking was force enabled, * {@code false} if follow-on locking was force disabled, * or {@code null} if the default behavior of the dialect * has not been overridden. * * @see org.hibernate.jpa.HibernateHints#HINT_FOLLOW_ON_LOCKING * @see org.hibernate.dialect.Dialect#useFollowOnLocking(String, QueryOptions) */ public Boolean getFollowOnLocking() { return followOnLocking; } /** * Force enable or disable the use of follow-on locking, * overriding the default behavior of the SQL dialect. * * @param followOnLocking The new follow-on locking setting * @return {@code this} for method chaining * * @see org.hibernate.jpa.HibernateHints#HINT_FOLLOW_ON_LOCKING * @see org.hibernate.dialect.Dialect#useFollowOnLocking(String, QueryOptions) */ public LockOptions setFollowOnLocking(Boolean followOnLocking) { if ( immutable ) { throw new UnsupportedOperationException("immutable global instance of LockMode"); } this.followOnLocking = followOnLocking; return this; } /** * Make a copy. * * @return The copy */ public LockOptions makeCopy() { final LockOptions copy = new LockOptions(); copy( this, copy ); return copy; } /** * Copy the given lock options into this instance, * merging the alias-specific lock modes. */ public void overlay(LockOptions lockOptions) { setLockMode( lockOptions.getLockMode() ); setScope( lockOptions.getScope() ); setTimeOut( lockOptions.getTimeOut() ); if ( lockOptions.aliasSpecificLockModes != null ) { lockOptions.aliasSpecificLockModes.forEach(this::setAliasSpecificLockMode); } setFollowOnLocking( lockOptions.getFollowOnLocking() ); } /** * Copy the options in the first given instance of * {@code LockOptions} to the second given instance. * * @param source Source for the copy (copied from) * @param destination Destination for the copy (copied to) * * @return destination */ public static LockOptions copy(LockOptions source, LockOptions destination) { destination.setLockMode( source.getLockMode() ); destination.setScope( source.getScope() ); destination.setTimeOut( source.getTimeOut() ); if ( source.aliasSpecificLockModes != null ) { destination.aliasSpecificLockModes = new HashMap<>( source.aliasSpecificLockModes ); } destination.setFollowOnLocking( source.getFollowOnLocking() ); return destination; } @Override public boolean equals(Object object) { if ( this == object ) { return true; } else if ( !(object instanceof LockOptions) ) { return false; } else { final LockOptions that = (LockOptions) object; return timeout == that.timeout && scope == that.scope && lockMode == that.lockMode && Objects.equals( aliasSpecificLockModes, that.aliasSpecificLockModes ) && Objects.equals( followOnLocking, that.followOnLocking ); } } @Override public int hashCode() { return Objects.hash( lockMode, timeout, aliasSpecificLockModes, followOnLocking, scope ); } }




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