com.redhat.ceylon.langtools.tools.javac.comp.Env Maven / Gradle / Ivy
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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 General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package com.redhat.ceylon.langtools.tools.javac.comp;
import java.util.Iterator;
import java.util.NoSuchElementException;
import com.redhat.ceylon.langtools.tools.javac.tree.*;
/** A class for environments, instances of which are passed as
* arguments to tree visitors. Environments refer to important ancestors
* of the subtree that's currently visited, such as the enclosing method,
* the enclosing class, or the enclosing toplevel node. They also contain
* a generic component, represented as a type parameter, to carry further
* information specific to individual passes.
*
* This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own risk.
* This code and its internal interfaces are subject to change or
* deletion without notice.
*/
public class Env implements Iterable> {
/** The next enclosing environment.
*/
public Env next;
/** The environment enclosing the current class.
*/
public Env outer;
/** The tree with which this environment is associated.
*/
public JCTree tree;
/** The enclosing toplevel tree.
*/
public JCTree.JCCompilationUnit toplevel;
/** The next enclosing class definition.
*/
public JCTree.JCClassDecl enclClass;
/** The next enclosing method definition.
*/
public JCTree.JCMethodDecl enclMethod;
/** A generic field for further information.
*/
public A info;
/** Is this an environment for evaluating a base clause?
*/
public boolean baseClause = false;
/** Create an outermost environment for a given (toplevel)tree,
* with a given info field.
*/
public Env(JCTree tree, A info) {
this.next = null;
this.outer = null;
this.tree = tree;
this.toplevel = null;
this.enclClass = null;
this.enclMethod = null;
this.info = info;
}
/** Duplicate this environment, updating with given tree and info,
* and copying all other fields.
*/
public Env dup(JCTree tree, A info) {
return dupto(new Env(tree, info));
}
/** Duplicate this environment into a given Environment,
* using its tree and info, and copying all other fields.
*/
public Env dupto(Env that) {
that.next = this;
that.outer = this.outer;
that.toplevel = this.toplevel;
that.enclClass = this.enclClass;
that.enclMethod = this.enclMethod;
return that;
}
/** Duplicate this environment, updating with given tree,
* and copying all other fields.
*/
public Env dup(JCTree tree) {
return dup(tree, this.info);
}
/** Return closest enclosing environment which points to a tree with given tag.
*/
public Env enclosing(int tag) {
Env env1 = this;
while (env1 != null && env1.tree.getTag() != tag) env1 = env1.next;
return env1;
}
public String toString() {
return "Env[" + info + (outer == null ? "" : ",outer=" + outer) + "]";
}
public Iterator> iterator() {
return new Iterator>() {
Env next = Env.this;
public boolean hasNext() {
return next.outer != null;
}
public Env next() {
if (hasNext()) {
Env current = next;
next = current.outer;
return current;
}
throw new NoSuchElementException();
}
public void remove() {
throw new UnsupportedOperationException();
}
};
}
}