Added @SneakyThrows support for javac. W00t.

This commit is contained in:
Reinier Zwitserloot committed 2009-07-01 22:36:50 +02:00
1 parent d174201c7f
commit 17d81608db
1 file changed
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package lombok.javac.handlers;
import static lombok.javac.handlers.PKG.chainDots;
import java.util.ArrayList;
import java.util.Collection;
import lombok.SneakyThrows;
import lombok.core.AnnotationValues;
import lombok.javac.JavacAnnotationHandler;
import lombok.javac.JavacAST.Node;
import org.mangosdk.spi.ProviderFor;
import com.sun.tools.javac.code.Flags;
import com.sun.tools.javac.tree.TreeMaker;
import com.sun.tools.javac.tree.JCTree.JCAnnotation;
import com.sun.tools.javac.tree.JCTree.JCAssign;
import com.sun.tools.javac.tree.JCTree.JCBlock;
import com.sun.tools.javac.tree.JCTree.JCExpression;
import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
import com.sun.tools.javac.tree.JCTree.JCNewArray;
import com.sun.tools.javac.tree.JCTree.JCStatement;
import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
import com.sun.tools.javac.util.List;
@ProviderFor(JavacAnnotationHandler.class)
public class HandleSneakyThrows implements JavacAnnotationHandler<SneakyThrows> {
@Override public boolean handle(AnnotationValues<SneakyThrows> annotation, JCAnnotation ast, Node annotationNode) {
Collection<String> exceptionNames = annotation.getRawExpressions("value");
List<JCExpression> memberValuePairs = ast.getArguments();
if ( memberValuePairs == null || memberValuePairs.size() == 0 ) return false;
JCExpression arrayOrSingle = ((JCAssign)memberValuePairs.get(0)).rhs;
final List<JCExpression> exceptionNameNodes;
if ( arrayOrSingle instanceof JCNewArray ) {
exceptionNameNodes = ((JCNewArray)arrayOrSingle).elems;
} else exceptionNameNodes = List.of(arrayOrSingle);
if ( exceptionNames.size() != exceptionNameNodes.size() ) {
annotationNode.addError(
"LOMBOK BUG: The number of exception classes in the annotation isn't the same pre- and post- guessing.");
}
java.util.List<String> exceptions = new ArrayList<String>();
for ( String exception : exceptionNames ) {
if ( exception.endsWith(".class") ) exception = exception.substring(0, exception.length() - 6);
exceptions.add(exception);
}
Node owner = annotationNode.up();
switch ( owner.getKind() ) {
case METHOD:
return handleMethod(annotationNode, (JCMethodDecl)owner.get(), exceptions);
default:
annotationNode.addError("@SneakyThrows is legal only on methods and constructors.");
return true;
}
}
private boolean handleMethod(Node annotation, JCMethodDecl method, Collection<String> exceptions) {
Node methodNode = annotation.up();
if ( (method.mods.flags & Flags.ABSTRACT) != 0 ) {
annotation.addError("@SneakyThrows can only be used on concrete methods.");
return true;
}
if ( method.body == null ) return false;
List<JCStatement> contents = method.body.stats;
for ( String exception : exceptions ) {
contents = List.of(buildTryCatchBlock(methodNode, contents, exception));
}
method.body.stats = contents;
methodNode.rebuild();
return true;
}
private JCStatement buildTryCatchBlock(Node node, List<JCStatement> contents, String exception) {
TreeMaker maker = node.getTreeMaker();
JCBlock tryBlock = maker.Block(0, contents);
JCExpression varType = chainDots(maker, node, exception.split("\\."));
JCVariableDecl catchParam = maker.VarDef(maker.Modifiers(0), node.toName("$ex"), varType, null);
JCExpression lombokLombokSneakyThrowNameRef = chainDots(maker, node, "lombok", "Lombok", "sneakyThrow");
JCBlock catchBody = maker.Block(0, List.<JCStatement>of(maker.Throw(maker.Apply(
List.<JCExpression>nil(), lombokLombokSneakyThrowNameRef,
List.<JCExpression>of(maker.Ident(node.toName("$ex")))))));
return maker.Try(tryBlock, List.of(maker.Catch(catchParam, catchBody)), null);
}
}