Package org.qubership.atp.dataset.db.migration.classloader

Class ParentLastClassloader

java.lang.Object

java.lang.ClassLoader

java.security.SecureClassLoader

java.net.URLClassLoader

org.qubership.atp.dataset.db.migration.classloader.ParentLastClassloader

All Implemented Interfaces:

Closeable, AutoCloseable

public class ParentLastClassloader
extends URLClassLoader

Constructor Summary

Constructors

Constructor	Description
ParentLastClassloader(URLClassLoader urlClassLoader, String sourcePath, String jdbcType)	ClassLoader based on URLClassLoader for loading classes from self.

Method Summary

Modifier and Type	Method	Description
Enumeration<URL>	getResources(String name)
Class<?>	loadClass(String className)	Load class from current classloader.
protected Class<?>	loadClass(String name, boolean resolve)
protected ChildClassLoader	refreshClassLoader(String className)

Methods inherited from class java.net.URLClassLoader

addURL, close, definePackage, findClass, findResource, findResources, getPermissions, getResourceAsStream, getURLs, newInstance, newInstance

Methods inherited from class java.security.SecureClassLoader

defineClass, defineClass

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findClass, findLibrary, findLoadedClass, findResource, findSystemClass, getClassLoadingLock, getDefinedPackage, getDefinedPackages, getName, getPackage, getPackages, getParent, getPlatformClassLoader, getResource, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, getUnnamedModule, isRegisteredAsParallelCapable, registerAsParallelCapable, resolveClass, resources, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

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

Constructor Details

ParentLastClassloader

public ParentLastClassloader(URLClassLoader urlClassLoader,
 String sourcePath,
 String jdbcType)

ClassLoader based on URLClassLoader for loading classes from self. In case class not found in this CL, it will try to load it from parent CL.

Parameters:

sourcePath - - location of resources. update.xml, migration scripts/jars etc. For example: ./scripts/

jdbcType - - type of database. This parameter need for loading generated q-classes. If you want use postgres database, and your jar with classes has name atp-dataset-q-classes-generation-pg.jar, then you must define jdbcType=pg When CL trying to load jar, it split the name on three parts: 1. general name = qubership-atp-dataset-q-classes-generation 2. suffix = pg 3. extension = .jar The suffix must match to jdbcType for loading this jar. So, you can check how it works in method createNewUrlClassLoader(List).

Method Details

getResources

public Enumeration<URL> getResources(String name)
                              throws IOException

Overrides:

getResources in class ClassLoader

Throws:

IOException

loadClass

protected Class<?> loadClass(String name,
 boolean resolve)
                      throws ClassNotFoundException

Overrides:

loadClass in class ClassLoader

Throws:

ClassNotFoundException

loadClass

public Class<?> loadClass(String className)
                   throws ClassNotFoundException

Load class from current classloader. In case the liquibase started executing new one changeset, then classloader will load compatible jars with q-classes and shaded jar with required dependencies. Which of q-classes jar will be loaded? It depends on jdbc_type.

Overrides:

loadClass in class ClassLoader

Parameters:

className - target class name.

Returns:

the Class

Throws:

ClassNotFoundException - in case Class not found in current and parent classloader.

refreshClassLoader

protected ChildClassLoader refreshClassLoader(String className)