net.sourceforge.pmd.lang.java.ast.ASTResource Maven / Gradle / Ivy
/**
* BSD-style license; for more info see http://pmd.sourceforge.net/license.html
*/
package net.sourceforge.pmd.lang.java.ast;
import org.checkerframework.checker.nullness.qual.Nullable;
import net.sourceforge.pmd.lang.ast.Node;
/**
* A resource of a {@linkplain ASTTryStatement try-with-resources}. This contains another
* node that represents the resource, according to the grammar below.
*
* In the case of concise try-with resources, the subexpressions are
* required to be only field accesses or variable references to compile.
*
*
*
* Resource ::= {@link ASTLocalVariableDeclaration LocalVariableDeclaration}
* | {@link ASTPrimaryExpression PrimaryExpression}
*
*
*/
public final class ASTResource extends AbstractJavaNode {
ASTResource(int id) {
super(id);
}
@Override
protected R acceptVisitor(JavaVisitor visitor, P data) {
return visitor.visit(this, data);
}
/**
* Returns true if this appears as an expression, and not as a
* local variable declaration.
*/
public boolean isConciseResource() {
return getChild(0) instanceof ASTExpression;
}
/**
* Gets the name with which the resource can be accessed in the
* body of the try statement. If this is a {@linkplain #isConciseResource() concise resource},
* then returns the sequence of names that identifies the expression.
* If this has a local variable declaration, then returns the name
* of the variable.
*/
public String getStableName() {
if (isConciseResource()) {
ASTExpression expr = getInitializer();
StringBuilder builder = new StringBuilder();
while (expr instanceof ASTFieldAccess) {
ASTFieldAccess fa = (ASTFieldAccess) expr;
builder.insert(0, "." + fa.getName());
expr = fa.getQualifier();
}
// the last one may be ambiguous, or a variable reference
// the only common interface we have to get their name is
// unfortunately Node::getImage
if (expr != null) {
builder.insert(0, expr.getImage());
}
return builder.toString();
} else {
return asLocalVariableDeclaration().iterator().next().getName();
}
}
@Nullable
public ASTLocalVariableDeclaration asLocalVariableDeclaration() {
return AstImplUtil.getChildAs(this, 0, ASTLocalVariableDeclaration.class);
}
/**
* Returns the initializer of the expression.
* If this is a concise resource, then returns that expression.
* If this is a local variable declaration, returns the initializer of
* the variable.
*/
public ASTExpression getInitializer() {
Node c = getChild(0);
if (c instanceof ASTExpression) {
return (ASTExpression) c;
} else {
return ((ASTLocalVariableDeclaration) c).iterator().next().getInitializer();
}
}
}