Java tutorial
//////////////////////////////////////////////////////////////////////////////// // checkstyle: Checks Java source code for adherence to a set of rules. // Copyright (C) 2001-2005 Oliver Burn // // This library is free software; you can redistribute it and/or // modify it under the terms of the GNU Lesser General Public // License as published by the Free Software Foundation; either // version 2.1 of the License, or (at your option) any later version. // // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // Lesser General Public License for more details. // // You should have received a copy of the GNU Lesser General Public // License along with this library; if not, write to the Free Software // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA //////////////////////////////////////////////////////////////////////////////// package jgraspcheckstyle.indentation; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.Set; import com.puppycrawl.tools.checkstyle.api.DetailAST; import com.puppycrawl.tools.checkstyle.api.TokenTypes; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Factory for handlers. Looks up constructor via reflection. * * @author jrichard */ public class HandlerFactory { /** Logger for indentation check */ private static final Log LOG = LogFactory.getLog("com.puppycrawl.tools.checkstyle.checks.indentation"); /** * Registered handlers. */ private final Map mTypeHandlers = new HashMap(); /** * registers a handler * * @param aType type from TokenTypes * @param aHandlerClass the handler to register */ private void register(int aType, Class aHandlerClass) { try { final Constructor ctor = aHandlerClass .getConstructor(new Class[] { IndentationCheck.class, DetailAST.class, // current AST ExpressionHandler.class, // parent }); mTypeHandlers.put(new Integer(aType), ctor); } ///CLOVER:OFF catch (NoSuchMethodException e) { throw new RuntimeException("couldn't find ctor for " + aHandlerClass); } catch (SecurityException e) { LOG.debug("couldn't find ctor for " + aHandlerClass, e); throw new RuntimeException("couldn't find ctor for " + aHandlerClass); } ///CLOVER:ON } /** Creates a HandlerFactory. */ public HandlerFactory() { register(TokenTypes.CASE_GROUP, CaseHandler.class); register(TokenTypes.LITERAL_SWITCH, SwitchHandler.class); register(TokenTypes.SLIST, SlistHandler.class); register(TokenTypes.PACKAGE_DEF, PackageDefHandler.class); register(TokenTypes.LITERAL_ELSE, ElseHandler.class); register(TokenTypes.LITERAL_IF, IfHandler.class); register(TokenTypes.LITERAL_TRY, TryHandler.class); register(TokenTypes.LITERAL_CATCH, CatchHandler.class); register(TokenTypes.LITERAL_FINALLY, FinallyHandler.class); register(TokenTypes.LITERAL_DO, DoWhileHandler.class); register(TokenTypes.LITERAL_WHILE, WhileHandler.class); register(TokenTypes.LITERAL_FOR, ForHandler.class); register(TokenTypes.METHOD_DEF, MethodDefHandler.class); register(TokenTypes.CTOR_DEF, MethodDefHandler.class); register(TokenTypes.CLASS_DEF, ClassDefHandler.class); register(TokenTypes.ENUM_DEF, ClassDefHandler.class); register(TokenTypes.OBJBLOCK, ObjectBlockHandler.class); register(TokenTypes.INTERFACE_DEF, ClassDefHandler.class); register(TokenTypes.IMPORT, ImportHandler.class); register(TokenTypes.ARRAY_INIT, ArrayInitHandler.class); register(TokenTypes.METHOD_CALL, MethodCallHandler.class); register(TokenTypes.CTOR_CALL, MethodCallHandler.class); register(TokenTypes.LABELED_STAT, LabelHandler.class); register(TokenTypes.STATIC_INIT, StaticInitHandler.class); register(TokenTypes.INSTANCE_INIT, SlistHandler.class); register(TokenTypes.ASSIGN, AssignHandler.class); register(TokenTypes.PLUS_ASSIGN, AssignHandler.class); register(TokenTypes.MINUS_ASSIGN, AssignHandler.class); register(TokenTypes.STAR_ASSIGN, AssignHandler.class); register(TokenTypes.DIV_ASSIGN, AssignHandler.class); register(TokenTypes.MOD_ASSIGN, AssignHandler.class); register(TokenTypes.SR_ASSIGN, AssignHandler.class); register(TokenTypes.BSR_ASSIGN, AssignHandler.class); register(TokenTypes.SL_ASSIGN, AssignHandler.class); register(TokenTypes.BAND_ASSIGN, AssignHandler.class); register(TokenTypes.BXOR_ASSIGN, AssignHandler.class); register(TokenTypes.BOR_ASSIGN, AssignHandler.class); register(TokenTypes.VARIABLE_DEF, MemberDefHandler.class); register(TokenTypes.LITERAL_NEW, NewHandler.class); } /** * Returns true if this type (form TokenTypes) is handled. * * @param aType type from TokenTypes * @return true if handler is registered, false otherwise */ public boolean isHandledType(int aType) { final Set typeSet = mTypeHandlers.keySet(); return typeSet.contains(new Integer(aType)); } /** * Gets list of registered handler types. * * @return int[] of TokenType types */ public int[] getHandledTypes() { final Set typeSet = mTypeHandlers.keySet(); final int[] types = new int[typeSet.size()]; int index = 0; for (final Iterator i = typeSet.iterator(); i.hasNext(); index++) { types[index] = ((Integer) i.next()).intValue(); } return types; } /** * Get the handler for an AST. * * @param aIndentCheck the indentation check * @param aAst ast to handle * @param aParent the handler parent of this AST * * @return the ExpressionHandler for aAst */ public ExpressionHandler getHandler(IndentationCheck aIndentCheck, DetailAST aAst, ExpressionHandler aParent) { final ExpressionHandler handler = (ExpressionHandler) mCreatedHandlers.get(aAst); if (handler != null) { return handler; } if (aAst.getType() == TokenTypes.METHOD_CALL) { return createMethodCallHandler(aIndentCheck, aAst, aParent); } final Integer type = new Integer(aAst.getType()); ExpressionHandler expHandler = null; try { final Constructor handlerCtor = (Constructor) mTypeHandlers.get(type); if (handlerCtor != null) { expHandler = (ExpressionHandler) handlerCtor .newInstance(new Object[] { aIndentCheck, aAst, aParent, }); } } ///CLOVER:OFF catch (InstantiationException e) { LOG.debug("couldn't instantiate constructor for " + aAst, e); throw new RuntimeException("couldn't instantiate constructor for " + aAst); } catch (IllegalAccessException e) { LOG.debug("couldn't access constructor for " + aAst, e); throw new RuntimeException("couldn't access constructor for " + aAst); } catch (InvocationTargetException e) { LOG.debug("couldn't instantiate constructor for " + aAst, e); throw new RuntimeException("couldn't instantiate constructor for " + aAst); } if (expHandler == null) { throw new RuntimeException("no handler for type " + type); } ///CLOVER:ON return expHandler; } /** * Create new instance of handler for METHOD_CALL. * * @param aIndentCheck the indentation check * @param aAst ast to handle * @param aParent the handler parent of this AST * * @return new instance. */ ExpressionHandler createMethodCallHandler(IndentationCheck aIndentCheck, DetailAST aAst, ExpressionHandler aParent) { DetailAST ast = (DetailAST) aAst.getFirstChild(); while ((ast != null) && (ast.getType() == TokenTypes.DOT)) { ast = (DetailAST) ast.getFirstChild(); } if ((ast != null) && isHandledType(ast.getType())) { aParent = getHandler(aIndentCheck, ast, aParent); mCreatedHandlers.put(ast, aParent); } return new MethodCallHandler(aIndentCheck, aAst, aParent); } /** Clears cache of created handlers. */ void clearCreatedHandlers() { mCreatedHandlers.clear(); } /** cache for created method call handlers */ private final Map mCreatedHandlers = new HashMap(); }