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package sun.jvm.hotspot.runtime;

import java.util.*;
import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.types.*;

This class provides generalized "virtual constructor" functionality for VMObjects. In simple terms, it creates correctly-typed Java wrapper objects for underlying Addresses, using the "RTTI-like" functionality of TypeDataBase. For example, if the given Address really is a DefNewGeneration*, the Java object created for it will be of type sun.jvm.hotspot.memory.DefNewGeneration, assuming the mapping from type "DefNewGeneration" to class sun.jvm.hotspot.memory.DefNewGeneration has been set up.
/** This class provides generalized "virtual constructor" functionality for VMObjects. In simple terms, it creates correctly-typed Java wrapper objects for underlying Addresses, using the "RTTI-like" functionality of TypeDataBase. For example, if the given Address really is a DefNewGeneration*, the Java object created for it will be of type sun.jvm.hotspot.memory.DefNewGeneration, assuming the mapping from type "DefNewGeneration" to class sun.jvm.hotspot.memory.DefNewGeneration has been set up. */
public class VirtualConstructor extends InstanceConstructor<VMObject> { private TypeDataBase db; private Map<String, Class<? extends VMObject>> map; public VirtualConstructor(TypeDataBase db) { this.db = db; map = new HashMap<>(); }
Adds a mapping from the given C++ type name to the given Java class. The latter must be a subclass of sun.jvm.hotspot.runtime.VMObject. Returns false if there was already a class for this type name in the map.
/** Adds a mapping from the given C++ type name to the given Java class. The latter must be a subclass of sun.jvm.hotspot.runtime.VMObject. Returns false if there was already a class for this type name in the map. */
public boolean addMapping(String cTypeName, Class<? extends VMObject> clazz) { if (map.get(cTypeName) != null) { return false; } map.put(cTypeName, clazz); return true; }
Instantiate the most-precisely typed wrapper object available for the type of the given Address. If no type in the mapping matched the type of the Address, throws a WrongTypeException. Returns null for a null address (similar behavior to VMObjectFactory).
/** Instantiate the most-precisely typed wrapper object available for the type of the given Address. If no type in the mapping matched the type of the Address, throws a WrongTypeException. Returns null for a null address (similar behavior to VMObjectFactory). */
public VMObject instantiateWrapperFor(Address addr) throws WrongTypeException { if (addr == null) { return null; } for (Iterator<String> iter = map.keySet().iterator(); iter.hasNext(); ) { String typeName = iter.next(); if (db.addressTypeIsEqualToType(addr, db.lookupType(typeName))) { return VMObjectFactory.newObject(map.get(typeName), addr); } } throw newWrongTypeException(addr); } }