/**
* Logback: the reliable, generic, fast and flexible logging framework.
* Copyright (C) 1999-2011, QOS.ch. All rights reserved.
*
* This program and the accompanying materials are dual-licensed under
* either the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation
*
* or (per the licensee's choosing)
*
* under the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation.
*/
package ch.qos.logback.core.joran.conditional;
import java.util.List;
import java.util.Stack;
import ch.qos.logback.core.util.EnvUtil;
import org.xml.sax.Attributes;
import ch.qos.logback.core.joran.action.Action;
import ch.qos.logback.core.joran.event.SaxEvent;
import ch.qos.logback.core.joran.spi.ActionException;
import ch.qos.logback.core.joran.spi.InterpretationContext;
import ch.qos.logback.core.joran.spi.Interpreter;
import ch.qos.logback.core.util.OptionHelper;
public class IfAction extends Action {
private static final String CONDITION_ATTR = "condition";
public static String MISSING_JANINO_MSG = "Could not find Janino library on the class path. Skipping conditional processing.";
Stack<IfState> stack = new Stack<IfState>();
@Override
public void begin(InterpretationContext ic, String name, Attributes attributes)
throws ActionException {
IfState state = new IfState();
boolean emptyStack = stack.isEmpty();
stack.push(state);
if(!emptyStack) {
return;
}
ic.pushObject(this);
if(!EnvUtil.isJaninoAvailable()) {
addError(MISSING_JANINO_MSG);
return;
}
state.active = true;
Condition condition = null;
String conditionAttribute = attributes.getValue(CONDITION_ATTR);
if (!OptionHelper.isEmpty(conditionAttribute)) {
conditionAttribute = OptionHelper.substVars(conditionAttribute, context);
PropertyEvalScriptBuilder pesb = new PropertyEvalScriptBuilder();
pesb.setContext(context);
try {
condition = pesb.build(conditionAttribute);
} catch (Exception e) {
addError("Faield to parse condition ["+conditionAttribute+"]", e);
}
if(condition!=null) {
state.boolResult = condition.evaluate();
}
}
}
@Override
public void end(InterpretationContext ic, String name) throws ActionException {
IfState state = stack.pop();
if(!state.active) {
return;
}
Object o = ic.peekObject();
if (o == null) {
throw new IllegalStateException("Unexpected null object on stack");
}
if (!(o instanceof IfAction)) {
throw new IllegalStateException("Unexpected object of type ["
+ o.getClass() + "] on stack");
}
if (o != this) {
throw new IllegalStateException(
"IfAction different then current one on stack");
}
ic.popObject();
if (state.boolResult == null) {
addError("Failed to determine \"if then else\" result");
return;
}
Interpreter interpreter = ic.getJoranInterpreter();
List<SaxEvent> listToPlay = state.thenSaxEventList;
if (!state.boolResult) {
listToPlay = state.elseSaxEventList;
}
// if boolResult==false & missing else, listToPlay may be null
if(listToPlay != null) {
// insert past this event
interpreter.getEventPlayer().addEventsDynamically(listToPlay, 1);
}
}
public void setThenSaxEventList(List<SaxEvent> thenSaxEventList) {
IfState state = stack.firstElement();
if(state.active) {
state.thenSaxEventList = thenSaxEventList;
} else {
throw new IllegalStateException("setThenSaxEventList() invoked on inactive IfAction");
}
}
public void setElseSaxEventList(List<SaxEvent> elseSaxEventList) {
IfState state = stack.firstElement();
if(state.active) {
state.elseSaxEventList = elseSaxEventList;
} else {
throw new IllegalStateException("setElseSaxEventList() invoked on inactive IfAction");
}
}
public boolean isActive() {
if(stack == null) return false;
if(stack.isEmpty()) return false;
return stack.peek().active;
}
}
class IfState {
Boolean boolResult;
List<SaxEvent> thenSaxEventList;
List<SaxEvent> elseSaxEventList;
boolean active;
}