Java tutorial
/** * * Copyright (c) 2014, the Railo Company Ltd. All rights reserved. * * 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, see <http://www.gnu.org/licenses/>. * **/ package lucee.transformer.bytecode.statement; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import lucee.runtime.type.scope.Scope; import lucee.transformer.bytecode.Body; import lucee.transformer.bytecode.BytecodeContext; import lucee.transformer.bytecode.BytecodeException; import lucee.transformer.bytecode.Position; import lucee.transformer.bytecode.expression.ExprString; import lucee.transformer.bytecode.expression.Expression; import lucee.transformer.bytecode.expression.var.DataMember; import lucee.transformer.bytecode.expression.var.Variable; import lucee.transformer.bytecode.expression.var.VariableRef; import lucee.transformer.bytecode.expression.var.VariableString; import lucee.transformer.bytecode.literal.LitBoolean; import lucee.transformer.bytecode.literal.LitString; import lucee.transformer.bytecode.statement.tag.TagTry; import lucee.transformer.bytecode.util.ExpressionUtil; import lucee.transformer.bytecode.util.Types; import lucee.transformer.bytecode.visitor.OnFinally; import lucee.transformer.bytecode.visitor.TryCatchFinallyVisitor; import org.objectweb.asm.Label; import org.objectweb.asm.Opcodes; import org.objectweb.asm.Type; import org.objectweb.asm.commons.GeneratorAdapter; import org.objectweb.asm.commons.Method; /** * produce try-catch-finally */ public final class TryCatchFinally extends StatementBase implements Opcodes, HasBodies, FlowControlRetry { //private static LitString ANY=LitString.toExprString("any", -1); private static final Method TO_PAGE_EXCEPTION = new Method("toPageException", Types.PAGE_EXCEPTION, new Type[] { Types.THROWABLE }); // public boolean typeEqual(String type); private static final Method TYPE_EQUAL = new Method("typeEqual", Types.BOOLEAN_VALUE, new Type[] { Types.STRING }); // Struct getCatchBlock(PageContext pc); private static final Method GET_CATCH_BLOCK = new Method("getCatchBlock", Types.STRUCT, new Type[] { Types.PAGE_CONTEXT }); // void isAbort(e) public static final Method IS_ABORT = new Method("isAbort", Types.BOOLEAN_VALUE, new Type[] { Types.THROWABLE }); private final static Method SET = new Method("set", Types.OBJECT, new Type[] { Types.PAGE_CONTEXT, Types.OBJECT }); private static final Method REMOVE_EL = new Method("removeEL", Types.OBJECT, new Type[] { Types.PAGE_CONTEXT }); private Body tryBody; private Body finallyBody; private List<Catch> catches = new ArrayList<Catch>(); private Position finallyLine; private Label begin = new Label(); private FlowControlFinal fcf; /** * Constructor of the class * @param body * @param line */ public TryCatchFinally(Body body, Position start, Position end) { super(start, end); this.tryBody = body; body.setParent(this); } /** * sets finally body * @param body */ public void setFinally(Body body, Position finallyLine) { body.setParent(this); this.finallyBody = body; this.finallyLine = finallyLine; } /** * data for a single catch block */ private class Catch { private ExprString type; private Body body; private VariableRef name; private Position line; public Catch(ExprString type, VariableRef name, Body body, Position line) { this.type = type; this.name = name; this.body = body; this.line = line; } } /** * * @see lucee.transformer.bytecode.statement.StatementBase#_writeOut(org.objectweb.asm.commons.GeneratorAdapter) */ public void _writeOut(BytecodeContext bc) throws BytecodeException { GeneratorAdapter adapter = bc.getAdapter(); adapter.visitLabel(begin); // Reference ref=null; final int lRef = adapter.newLocal(Types.REFERENCE); adapter.visitInsn(Opcodes.ACONST_NULL); adapter.storeLocal(lRef); // has no try body, if there is no try body, no catches are executed, only finally if (!tryBody.hasStatements()) { if (finallyBody != null) finallyBody.writeOut(bc); return; } TryCatchFinallyVisitor tcfv = new TryCatchFinallyVisitor(new OnFinally() { public void _writeOut(BytecodeContext bc) throws BytecodeException { _writeOutFinally(bc, lRef); } }, getFlowControlFinal()); // try tcfv.visitTryBegin(bc); tryBody.writeOut(bc); int lThrow = tcfv.visitTryEndCatchBeging(bc); _writeOutCatch(bc, lRef, lThrow); tcfv.visitCatchEnd(bc); } private void _writeOutFinally(BytecodeContext bc, int lRef) throws BytecodeException { // ref.remove(pc); //Reference r=null; GeneratorAdapter adapter = bc.getAdapter(); //if(fcf!=null && fcf.getAfterFinalGOTOLabel()!=null)ASMUtil.visitLabel(adapter,fcf.getFinalEntryLabel()); ExpressionUtil.visitLine(bc, finallyLine); //if (reference != null) // reference.removeEL(pagecontext); Label removeEnd = new Label(); adapter.loadLocal(lRef); adapter.ifNull(removeEnd); adapter.loadLocal(lRef); adapter.loadArg(0); adapter.invokeInterface(Types.REFERENCE, REMOVE_EL); adapter.pop(); adapter.visitLabel(removeEnd); if (finallyBody != null) finallyBody.writeOut(bc); // finally /*if(fcf!=null){ Label l = fcf.getAfterFinalGOTOLabel(); if(l!=null)adapter.visitJumpInsn(Opcodes.GOTO, l); }*/ } private void _writeOutCatch(BytecodeContext bc, int lRef, int lThrow) throws BytecodeException { GeneratorAdapter adapter = bc.getAdapter(); int pe = adapter.newLocal(Types.PAGE_EXCEPTION); // instance of Abort Label abortEnd = new Label(); adapter.loadLocal(lThrow); adapter.invokeStatic(Types.ABORT, TryCatchFinally.IS_ABORT); //adapter.instanceOf(Types.ABORT); adapter.ifZCmp(Opcodes.IFEQ, abortEnd); adapter.loadLocal(lThrow); adapter.throwException(); adapter.visitLabel(abortEnd); // PageExceptionImpl old=pc.getCatch(); int old = adapter.newLocal(Types.PAGE_EXCEPTION); adapter.loadArg(0); adapter.invokeVirtual(Types.PAGE_CONTEXT, TagTry.GET_CATCH); adapter.storeLocal(old); // cast to PageException Caster.toPagException(t); adapter.loadLocal(lThrow); adapter.invokeStatic(Types.CASTER, TO_PAGE_EXCEPTION); // PageException pe=... adapter.storeLocal(pe); // catch loop Label endAllIf = new Label(); Iterator<Catch> it = catches.iterator(); Catch ctElse = null; while (it.hasNext()) { Catch ct = it.next(); // store any for else if (ct.type != null && ct.type instanceof LitString && ((LitString) ct.type).getString().equalsIgnoreCase("any")) { ctElse = ct; continue; } ExpressionUtil.visitLine(bc, ct.line); // pe.typeEqual(type) if (ct.type == null) { LitBoolean.TRUE.writeOut(bc, Expression.MODE_VALUE); } else { adapter.loadLocal(pe); ct.type.writeOut(bc, Expression.MODE_REF); adapter.invokeVirtual(Types.PAGE_EXCEPTION, TYPE_EQUAL); } Label endIf = new Label(); adapter.ifZCmp(Opcodes.IFEQ, endIf); catchBody(bc, adapter, ct, pe, lRef, true, true); adapter.visitJumpInsn(Opcodes.GOTO, endAllIf); adapter.visitLabel(endIf); } if (ctElse != null) { catchBody(bc, adapter, ctElse, pe, lRef, true, true); } else { // pc.setCatch(pe,true); adapter.loadArg(0); adapter.loadLocal(pe); adapter.push(false); adapter.push(false); adapter.invokeVirtual(Types.PAGE_CONTEXT, TagTry.SET_CATCH3); adapter.loadLocal(pe); adapter.throwException(); } adapter.visitLabel(endAllIf); // PageExceptionImpl old=pc.setCatch(old); adapter.loadArg(0); adapter.loadLocal(old); adapter.invokeVirtual(Types.PAGE_CONTEXT, TagTry.SET_CATCH_PE); } private static void catchBody(BytecodeContext bc, GeneratorAdapter adapter, Catch ct, int pe, int lRef, boolean caugth, boolean store) throws BytecodeException { // pc.setCatch(pe,true); adapter.loadArg(0); adapter.loadLocal(pe); adapter.push(caugth); adapter.push(store); adapter.invokeVirtual(Types.PAGE_CONTEXT, TagTry.SET_CATCH3); // ref= ct.name.writeOut(bc, Expression.MODE_REF); adapter.storeLocal(lRef); adapter.loadLocal(lRef); adapter.loadArg(0); adapter.loadLocal(pe);// (...,pe.getCatchBlock(pc)) adapter.loadArg(0); adapter.invokeVirtual(Types.PAGE_EXCEPTION, GET_CATCH_BLOCK); adapter.invokeInterface(Types.REFERENCE, SET); adapter.pop(); ct.body.writeOut(bc); } /** * @param type * @param name * @param body * @param line */ public void addCatch(ExprString type, VariableRef name, Body body, Position line) { body.setParent(this); catches.add(new Catch(type, name, body, line)); } /** * @param type * @param name * @param b * @param line * @throws BytecodeException */ public void addCatch(Expression type, Expression name, Body b, Position line) throws BytecodeException { // type if (type == null || type instanceof ExprString) ; else if (type instanceof Variable) { type = VariableString.toExprString(type); } else throw new BytecodeException("type from catch statement is invalid", type.getStart()); // name if (name instanceof LitString) { Variable v = new Variable(Scope.SCOPE_UNDEFINED, name.getStart(), name.getEnd()); v.addMember(new DataMember(name)); name = new VariableRef(v); } else if (name instanceof Variable) name = new VariableRef((Variable) name); else throw new BytecodeException("name from catch statement is invalid", name.getStart()); addCatch((ExprString) type, (VariableRef) name, b, line); } /** * @see lucee.transformer.bytecode.statement.HasBodies#getBodies() */ public Body[] getBodies() { int len = catches.size(), count = 0; if (tryBody != null) len++; if (finallyBody != null) len++; Body[] bodies = new Body[len]; Catch c; Iterator<Catch> it = catches.iterator(); while (it.hasNext()) { c = it.next(); bodies[count++] = c.body; } if (tryBody != null) bodies[count++] = tryBody; if (finallyBody != null) bodies[count++] = finallyBody; return bodies; } @Override public FlowControlFinal getFlowControlFinal() { if (fcf == null) fcf = new FlowControlFinalImpl(); return fcf; } @Override public Label getRetryLabel() { return begin; } @Override public String getLabel() { return null; } }