/**
* MVEL 2.0
* Copyright (C) 2007 The Codehaus
* Mike Brock, Dhanji Prasanna, John Graham, Mark Proctor
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.mvel2.ast;
import org.mvel2.CompileException;
import org.mvel2.ParserContext;
import org.mvel2.compiler.ExecutableStatement;
import org.mvel2.integration.VariableResolverFactory;
import org.mvel2.integration.impl.MapVariableResolverFactory;
import org.mvel2.util.ParseTools;
import java.util.HashMap;
import static org.mvel2.util.CompilerTools.expectType;
import static org.mvel2.util.ParseTools.subCompileExpression;
/**
* @author Christopher Brock
*/
public class ForNode extends BlockNode {
protected String item;
protected ExecutableStatement initializer;
protected ExecutableStatement condition;
protected ExecutableStatement after;
protected boolean indexAlloc = false;
public ForNode(char[] expr, int start, int offset, int blockStart, int blockEnd, int fields, ParserContext pCtx) {
super(pCtx);
boolean varsEscape = buildForEach(this.expr = expr, this.start = start, this.offset = offset,
this.blockStart = blockStart, this.blockOffset = blockEnd, fields, pCtx);
this.indexAlloc = pCtx != null && pCtx.isIndexAllocation();
if ((fields & COMPILE_IMMEDIATE) != 0 && compiledBlock.isEmptyStatement() && !varsEscape) {
throw new RedundantCodeException();
}
if (pCtx != null) {
pCtx.popVariableScope();
}
}
public Object getReducedValueAccelerated(Object ctx, Object thisValue, VariableResolverFactory factory) {
VariableResolverFactory ctxFactory = indexAlloc ? factory : new MapVariableResolverFactory(new HashMap<String, Object>(1), factory);
Object v;
for (initializer.getValue(ctx, thisValue, ctxFactory); (Boolean) condition.getValue(ctx, thisValue, ctxFactory); after.getValue(ctx, thisValue, ctxFactory)) {
v = compiledBlock.getValue(ctx, thisValue, ctxFactory);
if (ctxFactory.tiltFlag()) return v;
}
return null;
}
public Object getReducedValue(Object ctx, Object thisValue, VariableResolverFactory factory) {
Object v;
for (initializer.getValue(ctx, thisValue, factory = new MapVariableResolverFactory(new HashMap<String, Object>(1), factory)); (Boolean) condition.getValue(ctx, thisValue, factory); after.getValue(ctx, thisValue, factory)) {
v = compiledBlock.getValue(ctx, thisValue, factory);
if (factory.tiltFlag()) return v;
}
return null;
}
private boolean buildForEach(char[] condition, int start, int offset, int blockStart, int blockEnd, int fields, ParserContext pCtx) {
int end = start + offset;
int cursor = nextCondPart(condition, start, end, false);
boolean varsEscape = false;
try {
ParserContext spCtx;
if (pCtx != null) {
spCtx = pCtx.createSubcontext().createColoringSubcontext();
}
else {
spCtx = new ParserContext();
}
this.initializer = (ExecutableStatement) subCompileExpression(condition, start, cursor - start - 1, spCtx);
if (pCtx != null) {
pCtx.pushVariableScope();
}
try {
expectType(this.condition = (ExecutableStatement) subCompileExpression(condition, start = cursor,
(cursor = nextCondPart(condition, start, end, false)) - start - 1, spCtx), Boolean.class, ((fields & COMPILE_IMMEDIATE) != 0));
}
catch (CompileException e) {
if (e.getExpr().length == 0) {
e.setExpr(expr);
while (start < expr.length && ParseTools.isWhitespace(expr[start])) {
start++;
}
e.setCursor(start);
}
throw e;
}
this.after = (ExecutableStatement)
subCompileExpression(condition, start = cursor, (nextCondPart(condition, start, end, true)) - start, spCtx);
if (spCtx != null && (fields & COMPILE_IMMEDIATE) != 0 && spCtx.isVariablesEscape()) {
if (pCtx != spCtx) pCtx.addVariables(spCtx.getVariables());
varsEscape = true;
}
else if (spCtx != null && pCtx != null) {
pCtx.addVariables(spCtx.getVariables());
}
this.compiledBlock = (ExecutableStatement) subCompileExpression(expr, blockStart, blockEnd, spCtx);
if (pCtx != null) {
pCtx.setInputs(spCtx.getInputs());
}
}
catch (NegativeArraySizeException e) {
throw new CompileException("wrong syntax; did you mean to use 'foreach'?", expr, start);
}
return varsEscape;
}
private static int nextCondPart(char[] condition, int cursor, int end, boolean allowEnd) {
for (; cursor < end; cursor++) {
if (condition[cursor] == ';') return ++cursor;
}
if (!allowEnd) throw new CompileException("expected ;", condition, cursor);
return cursor;
}
}