/*
* Copyright 2009 Google Inc.
*
* 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 com.google.gwt.dev.jjs.impl.gflow.cfg;
/**
* Edge in CFG graph. Edge can be annotated by its role when there are several
* edges coming from the node, to be able to reason about them separately (e.g.
* it's important which edge is then/else branch in conditional node).
*/
public class CfgEdge {
Object data;
// We do not add setStart/setEnd methods because we'd like to be sure
// that no one except CfgNode changes these.
CfgNode<?> end;
CfgNode<?> start;
private final String role;
public CfgEdge() {
this.role = null;
}
public CfgEdge(String role) {
this.role = role;
}
/**
* Get edge end node.
*/
public CfgNode<?> getEnd() {
return end;
}
/**
* Get edge role.
*/
public String getRole() {
return role;
}
/**
* Get edge start node.
*/
public CfgNode<?> getStart() {
return start;
}
@Override
public String toString() {
return (start != null ? start.toDebugString() : "*") + "->" +
(end != null ? end.toDebugString() : "*");
}
}