com.goldencode.p2j.persist

Class DynamicTablesHelper

java.lang.Object

com.goldencode.p2j.persist.DynamicTablesHelper

public class DynamicTablesHelper
extends java.lang.Object

Helper class for dynamic temporary tables.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	DynamicTablesHelper.CacheData DMO data to be cached for a dynamically defined temp-table.
private static class	DynamicTablesHelper.CacheKey A hashable key that encapsulates the characteristics which uniquely define the structure of a dynamic temp-table; namely, its field and index definitions.
private class	DynamicTablesHelper.Context Context local information, used to clean up resources when the context ends and to respond to queries about temp-table resources in use.
private static class	DynamicTablesHelper.DMOInfo Class which contains information about a dynamically define DMO, including the compiled interface and implementation classes, and mappings between the legacy and converted fields.
private class	DynamicTablesHelper.DMOResourceManager An instance of this class manages resources requiring cleanup, across all contexts.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Map<DynamicTablesHelper.CacheKey,DynamicTablesHelper.CacheData>	cache Cache for dynamically converted and compiled DMO resources
private java.lang.Object	cacheLock Lock object on which to synchronize cache operations
private ContextLocal<DynamicTablesHelper.Context>	context Containers for context-specific data.
private java.util.List<java.io.File>	createdDirectories List of directories that are newly created.
(package private) static java.lang.String	DMO_BASE_PACKAGE Base package for generated DMOs.
(package private) static java.lang.String	DMO_IFACE_CATEGORY Category name for DMO interfaces, used in conversion rules.
private DynamicTablesHelper.DMOResourceManager	dmoResourceManager Cross-context manager which cleans up shared DMO resources once they go out of scope
private static java.util.Set<java.lang.String>	existingEntries List of entries present in the jar.
private static DynamicTablesHelper	instance Singleton instance.
private static CentralLogger	LOG Logger.
private java.io.File	persistentCacheJarFile File object corresponding to the jar file with dynamic table DMO classes.
private java.lang.String	persistentCacheJarPath Path to the jar file where dynamic table DMO classes will be placed at server shutdown.
private java.util.Map<java.lang.String,java.util.List<java.lang.String>>	persistentCacheMap Cache used to find out if a dynamic table DMO needs to be assembled or exists saved on disk.
private java.io.File	persistentCacheMapFile File object corresponding to the file with data used to identify cached dynamic table DMO classes.
private java.lang.String	persistentCacheMapPath Path to the file containing data used to identify cached dynamic table DMO classes.
(package private) static java.util.Map<ParmType,java.lang.Integer>	propTypeToProgress Param type to Progress type.
private static AsmClassLoader	systemInMemoryClassLoader In-memory class loader
private java.util.concurrent.atomic.AtomicLong	tableCounter Counter used for generation of unique names for dynamic tables.
private java.lang.String	tempLibFilePath Name of a temporary directory where .class files of dynamic table DMO classes are saved.
private java.lang.String	temporaryJarName Path to the jar file that will temprarily exist at server shutdown.
private boolean	usePersistentCache Marks if dynamic table DMO classes generated will be saved to/read from a persistent cache.

Constructor Summary

Constructors

Modifier	Constructor and Description
private	DynamicTablesHelper() Private constructor to enforce singleton.

Method Summary

Modifier and Type	Method and Description
(package private) static long	assignIds(Aast root, long startId) Traverse an AST and assign unique IDs to all of its nodes.
private void	cleanupDirectories() Cleans up newly created directories.
void	createCache() Method meant to create a Jar file containing dynamic table classes that were cached to disk, so that they are not generated every time the server is started.
private void	createCacheHelper(java.io.File source, java.util.jar.JarOutputStream target, java.util.Set<java.lang.String> packages) Helper method for creating the dynamic table classes jar/cache.
private void	createDirectoryHierarchy(java.io.File dir) Ensures the directory hierarchy exists by creating any missing directories.
(package private) boolean	createDynamicDMO(TempTableBuilder builder, java.lang.String legacyTableName, java.lang.String legacyPeerName, boolean isBeforeTable) Generate DMO interface, implementation class and mapping document and register the new DMO type.
(package private) void	deregisterBuilder(TempTableBuilder builder) Deregister the given temp-table builder from the DMO resource manager.
(package private) void	deregisterDmoUser(TempTableBuilder builder) Remove this dynamic temp-table from the DMO users.
private void	extractIndexes(DmoMeta dmoMeta, java.util.ArrayList<P2JIndex> fwdIndexes) Extracts the list of indexes from an interface into an array.
(package private) static Persistence	findExistingTable(java.lang.String fullTableName) Search for an existing table with the specified name.
private static Persistence	findMetaPersistence(java.lang.String pdb, java.lang.String tableName) Find the Persistence object that is associated with the given database and table.
(package private) Aast	generateSchemaAst(TempTableBuilder builder, java.lang.String ifaceName, java.lang.String tableName, java.lang.String legacyTableName, java.util.Map<java.lang.String,java.lang.String> fields4GLtoORM, java.lang.String legacyPeerName, boolean isBeforeTable) Generate AST that represents the target table and has the same structure as .p2o files from the conversion stage.
(package private) static java.lang.String	get4GLFieldName(java.lang.Class<? extends DataModelObject> dmoIface, java.lang.String dmoFieldName) Get 4GL field name by DMO field name for a dynamic DMO.
(package private) static java.lang.String	get4GLTableName(Persistence persistence, java.lang.String tableName4GL) Get original 4GL table name.
(package private) static java.lang.String	getHibernateFieldName(java.lang.Class<? extends DataModelObject> dmoIface, int fieldId) Get DMO field name by field creation id for a dynamic DMO.
(package private) static java.lang.String	getHibernateFieldName(java.lang.Class<? extends DataModelObject> dmoIface, java.lang.String name4gl) Get DMO field name by 4GL field name for a dynamic DMO.
static DynamicTablesHelper	getInstance() Get singleton instance of the helper.
(package private) static TempTableBuilder	getTableInfo(RecordBuffer buffer) Returns the TempTableBuilder object that contains information about the 4GL representation of the table or null if there is no corresponding dynamic table for the specified record buffer.
private void	initializePersistentCacheData() Method called at class initialization, meant to read from disk the data regarding the dynamic table classes cache, saved in the form of a HashMap object.
(package private) static boolean	isDynamicTableBuffer(RecordBuffer buffer) Allows to determine if the buffer is for a dynamic table.
(package private) static java.lang.String[]	parseTableName(java.lang.String fullTableName) Get table name and database name from the string which represents full table name
private static java.lang.String	rightTrim(java.lang.String str) Convenience method to remove trailing whitespace (space, tab, line feed, carriage return) from the string.
private void	saveDynamicDmoToDisk(java.lang.String className, byte[] code) Method used to save to disk a dynamic table class generated at runtime as a .class file.
(package private) static boolean	tableExists(Persistence persistence, java.lang.String tableName4GL) Determines if the specified table exists.
private void	updatePersistentCacheMap() Method used to update/create the file on disk that retains data about the dynamic table classes cache, in the form of a HashMap object.
private static void	writeJarIndex(java.util.jar.JarOutputStream jos, java.util.Set<java.lang.String> packages) Writes the jar index to the jar file's META-INF directory.

Methods inherited from class java.lang.Object

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

Field Detail

DMO_BASE_PACKAGE

static final java.lang.String DMO_BASE_PACKAGE

Base package for generated DMOs.

See Also:

Constant Field Values

DMO_IFACE_CATEGORY

static final java.lang.String DMO_IFACE_CATEGORY

Category name for DMO interfaces, used in conversion rules.

See Also:

Constant Field Values

propTypeToProgress

static final java.util.Map<ParmType,java.lang.Integer> propTypeToProgress

Param type to Progress type.

LOG

private static final CentralLogger LOG

Logger.

instance

private static volatile DynamicTablesHelper instance

Singleton instance.

systemInMemoryClassLoader

private static AsmClassLoader systemInMemoryClassLoader

In-memory class loader

cache

private final java.util.Map<DynamicTablesHelper.CacheKey,DynamicTablesHelper.CacheData> cache

Cache for dynamically converted and compiled DMO resources

cacheLock

private final java.lang.Object cacheLock

Lock object on which to synchronize cache operations

persistentCacheMap

private java.util.Map<java.lang.String,java.util.List<java.lang.String>> persistentCacheMap

Cache used to find out if a dynamic table DMO needs to be assembled or exists saved on disk. The key is a string value of a CacheKey object. The value is a list, starting with an id, and followed by the names of all the interface names used to generate the DMO class.

usePersistentCache

private boolean usePersistentCache

Marks if dynamic table DMO classes generated will be saved to/read from a persistent cache.

tempLibFilePath

private java.lang.String tempLibFilePath

Name of a temporary directory where .class files of dynamic table DMO classes are saved.

persistentCacheJarPath

private java.lang.String persistentCacheJarPath

Path to the jar file where dynamic table DMO classes will be placed at server shutdown.

persistentCacheMapPath

private java.lang.String persistentCacheMapPath

Path to the file containing data used to identify cached dynamic table DMO classes.

temporaryJarName

private java.lang.String temporaryJarName

Path to the jar file that will temprarily exist at server shutdown.

persistentCacheJarFile

private java.io.File persistentCacheJarFile

File object corresponding to the jar file with dynamic table DMO classes.

createdDirectories

private java.util.List<java.io.File> createdDirectories

List of directories that are newly created.

existingEntries

private static java.util.Set<java.lang.String> existingEntries

List of entries present in the jar.

persistentCacheMapFile

private java.io.File persistentCacheMapFile

File object corresponding to the file with data used to identify cached dynamic table DMO classes.

context

private final ContextLocal<DynamicTablesHelper.Context> context

Containers for context-specific data.

tableCounter

private final java.util.concurrent.atomic.AtomicLong tableCounter

Counter used for generation of unique names for dynamic tables.

dmoResourceManager

private final DynamicTablesHelper.DMOResourceManager dmoResourceManager

Cross-context manager which cleans up shared DMO resources once they go out of scope

Constructor Detail

DynamicTablesHelper

private DynamicTablesHelper()

Private constructor to enforce singleton.

Method Detail

getInstance

public static DynamicTablesHelper getInstance()

Get singleton instance of the helper.

Returns:

singleton instance of the helper.

getHibernateFieldName

static java.lang.String getHibernateFieldName(java.lang.Class<? extends DataModelObject> dmoIface,
                                              java.lang.String name4gl)

Get DMO field name by 4GL field name for a dynamic DMO.

Parameters:

dmoIface - DMO interface that corresponds the target dynamic DMO class.

name4gl - 4GL field name.

Returns:

DMO field name for the given DMO class and 4GL field name or null if no corresponding name was found.

getHibernateFieldName

static java.lang.String getHibernateFieldName(java.lang.Class<? extends DataModelObject> dmoIface,
                                              int fieldId)

Get DMO field name by field creation id for a dynamic DMO.

Parameters:

dmoIface - DMO interface that corresponds the target dynamic DMO class.

fieldId - 4GL field id.

Returns:

DMO field name for the given DMO class and 4GL field name or null if no corresponding name was found.

get4GLFieldName

static java.lang.String get4GLFieldName(java.lang.Class<? extends DataModelObject> dmoIface,
                                        java.lang.String dmoFieldName)

Get 4GL field name by DMO field name for a dynamic DMO.

Parameters:

dmoIface - DMO interface that corresponds the target dynamic DMO class.

dmoFieldName - DMO field name.

Returns:

4GL field name for the given DMO class and DMO field name or null if no corresponding name was found.

parseTableName

static java.lang.String[] parseTableName(java.lang.String fullTableName)

Get table name and database name from the string which represents full table name

Parameters:

fullTableName - The string which represents full table name. Can have two formats: "databaseName.tableName" or "tableName".

Returns:

String array with two elements. The first element is table name. The second element is database name or null if the database name wasn't specified in the full table name.

isDynamicTableBuffer

static boolean isDynamicTableBuffer(RecordBuffer buffer)

Allows to determine if the buffer is for a dynamic table.

Parameters:

buffer - Buffer to check.

Returns:

true if buffer is for a dynamic table.

getTableInfo

static TempTableBuilder getTableInfo(RecordBuffer buffer)

Returns the TempTableBuilder object that contains information about the 4GL representation of the table or null if there is no corresponding dynamic table for the specified record buffer.

Parameters:

buffer - Record buffer that corresponds to the target dynamic table.

Returns:

See above.

tableExists

static boolean tableExists(Persistence persistence,
                           java.lang.String tableName4GL)

Determines if the specified table exists.

Parameters:

persistence - Persistence which corresponds the target database.

tableName4GL - 4GL table name.

Returns:

true if the specified table exists.

findExistingTable

static Persistence findExistingTable(java.lang.String fullTableName)

Search for an existing table with the specified name.

Parameters:

fullTableName - Table name in format "databaseName.tableName" or "tableName". In the latter case table search is performed in all permanent databases and then the temporary database. Dynamic tables are ignored.

Returns:

persistence which corresponds the target database or null if there is no such table.

get4GLTableName

static java.lang.String get4GLTableName(Persistence persistence,
                                        java.lang.String tableName4GL)

Get original 4GL table name. Despite the fact that we specify 4GL table name as an input parameter, this parameter can have different letter case or may have trailing spaces (this form is allowed when specifying table name in 4GL code).

Parameters:

persistence - Persistence which corresponds the target database.

tableName4GL - 4GL table name (case-insensitive, may have trailing spaces).

Returns:

original 4GL table name.

assignIds

static long assignIds(Aast root,
                      long startId)

Traverse an AST and assign unique IDs to all of its nodes.

Parameters:

root - The root node of the AST.

startId - First available id for assignment.

Returns:

new first available id for assignment.

findMetaPersistence

private static Persistence findMetaPersistence(java.lang.String pdb,
                                               java.lang.String tableName)

Find the Persistence object that is associated with the given database and table.

Parameters:

pdb - Physical database name of primary database.

tableName - Unqualified table name.

Returns:

Persistence object if table is found

rightTrim

private static java.lang.String rightTrim(java.lang.String str)

Convenience method to remove trailing whitespace (space, tab, line feed, carriage return) from the string.

Parameters:

str - Target string.

Returns:

the target string without trailing spaces.

saveDynamicDmoToDisk

private void saveDynamicDmoToDisk(java.lang.String className,
                                  byte[] code)

Method used to save to disk a dynamic table class generated at runtime as a .class file.

Parameters:

className - The name of the newly generated class that will be saved to disk.

code - The contents of the class file as a byte array.

initializePersistentCacheData

private void initializePersistentCacheData()

Method called at class initialization, meant to read from disk the data regarding the dynamic table classes cache, saved in the form of a HashMap object.

updatePersistentCacheMap

private void updatePersistentCacheMap()

Method used to update/create the file on disk that retains data about the dynamic table classes cache, in the form of a HashMap object.

createCache

public void createCache()

Method meant to create a Jar file containing dynamic table classes that were cached to disk, so that they are not generated every time the server is started. It creates a temporary jar file, copies all the classes from the old jar file, if it exists, then takes all the new classes generated that are saved in a folder that is then deleted. The old jar file is deleted, and the temporary jar file is renamed to match the old one.

createDirectoryHierarchy

private void createDirectoryHierarchy(java.io.File dir)

Ensures the directory hierarchy exists by creating any missing directories. Newly created directories are tracked for cleanup later.

Parameters:

dir - The directory to create.

cleanupDirectories

private void cleanupDirectories()

Cleans up newly created directories.

createCacheHelper

private void createCacheHelper(java.io.File source,
                               java.util.jar.JarOutputStream target,
                               java.util.Set<java.lang.String> packages)
                        throws java.io.IOException

Helper method for creating the dynamic table classes jar/cache. Receives the file/directory to be added to the jar, and the stream used to write to the jar. Calls itself recursively for every directory in the source File, if that is a directory. Otherwise, it adds the source File to the jar.

Parameters:

source - The class file or directory containing class files that will be added to the jar.

target - The stream used to add files to the jar.

packages - The set to collect package names.

Throws:

java.io.IOException - Exception that can be thrown by the JarOutputStream object, not handled here.

writeJarIndex

private static void writeJarIndex(java.util.jar.JarOutputStream jos,
                                  java.util.Set<java.lang.String> packages)
                           throws java.io.IOException

Writes the jar index to the jar file's META-INF directory.

Parameters:

jos - The JarOutputStream to write the index to.

packages - The set of package names to include in the index.

Throws:

java.io.IOException - Exception that can be thrown by the JarOutputStream object, not handled here.

createDynamicDMO

boolean createDynamicDMO(TempTableBuilder builder,
                         java.lang.String legacyTableName,
                         java.lang.String legacyPeerName,
                         boolean isBeforeTable)

Generate DMO interface, implementation class and mapping document and register the new DMO type. If requested, also caches the new classes generated to disk.

Parameters:

builder - Temporary table builder containing definitions of the target table.

legacyTableName - The legacy name of the table.

legacyPeerName - The legacy name of the table's peer. May be null.

isBeforeTable - Flag indicating the DMO is being built for a before table.

Returns:

true on success.

deregisterBuilder

void deregisterBuilder(TempTableBuilder builder)

Deregister the given temp-table builder from the DMO resource manager.

Parameters:

builder - Builder to be deregistered.

deregisterDmoUser

void deregisterDmoUser(TempTableBuilder builder)

Remove this dynamic temp-table from the DMO users.

Parameters:

builder - Builder to be deregistered.

extractIndexes

private void extractIndexes(DmoMeta dmoMeta,
                            java.util.ArrayList<P2JIndex> fwdIndexes)

Extracts the list of indexes from an interface into an array.

Parameters:

dmoMeta - the metadata collection of the DMO interface.

fwdIndexes - The destination array where the index data will be stored.

generateSchemaAst

Aast generateSchemaAst(TempTableBuilder builder,
                       java.lang.String ifaceName,
                       java.lang.String tableName,
                       java.lang.String legacyTableName,
                       java.util.Map<java.lang.String,java.lang.String> fields4GLtoORM,
                       java.lang.String legacyPeerName,
                       boolean isBeforeTable)

Generate AST that represents the target table and has the same structure as .p2o files from the conversion stage.

Parameters:

builder - Temporary table builder containing definitions of the target table.

ifaceName - The name of the target DMO interface.

tableName - The name of the target SQL table.

legacyTableName - The legacy (Progress) name of the table.

fields4GLtoORM - Map 4GL field names to ORM names.

legacyPeerName - The legacy name of the table's peer. May be null.

isBeforeTable - Flag indicating the DMO is being built for a before table.

Returns:

the root node of the generated AST.