Add postprocessing chain

4 files changed, 62 insertions, 56 deletions

diff --git a/javaparser-core/src/main/java/com/github/javaparser/JavaParser.java b/javaparser-core/src/main/java/com/github/javaparser/JavaParser.java
index 287e88e6b..7b8ee87a5 100644
--- a/javaparser-core/src/main/java/com/github/javaparser/JavaParser.java
+++ b/javaparser-core/src/main/java/com/github/javaparser/JavaParser.java
@@ -27,16 +27,13 @@ import com.github.javaparser.ast.Node;
 import com.github.javaparser.ast.PackageDeclaration;
 import com.github.javaparser.ast.body.BodyDeclaration;
 import com.github.javaparser.ast.body.Parameter;
-import com.github.javaparser.ast.comments.CommentsCollection;
 import com.github.javaparser.ast.expr.*;
 import com.github.javaparser.ast.stmt.BlockStmt;
 import com.github.javaparser.ast.stmt.ExplicitConstructorInvocationStmt;
 import com.github.javaparser.ast.stmt.Statement;
 import com.github.javaparser.ast.type.ClassOrInterfaceType;
 import com.github.javaparser.ast.type.Type;
-import com.github.javaparser.ast.validator.ProblemReporter;
 import com.github.javaparser.javadoc.Javadoc;
-import com.github.javaparser.printer.lexicalpreservation.LexicalPreservingPrinter;
 
 import java.io.*;
 import java.nio.charset.Charset;
@@ -53,7 +50,6 @@ import static com.github.javaparser.utils.Utils.assertNotNull;
  * @author Júlio Vilmar Gesser
  */
 public final class JavaParser {
-    private final CommentsInserter commentsInserter;
     private final ParserConfiguration configuration;
 
     private GeneratedJavaParser astParser = null;
@@ -74,7 +70,6 @@ public final class JavaParser {
      */
     public JavaParser(ParserConfiguration configuration) {
         this.configuration = configuration;
-        commentsInserter = new CommentsInserter(configuration);
     }
 
     /**
@@ -129,20 +124,13 @@ public final class JavaParser {
         final GeneratedJavaParser parser = getParserForProvider(provider);
         try {
             N resultNode = start.parse(parser);
-            if (configuration.isAttributeComments()) {
-                final CommentsCollection comments = parser.getCommentsCollection();
-                commentsInserter.insertComments(resultNode, comments.copy().getComments());
-            }
-            if (configuration.isLexicalPreservationEnabled()) {
-                LexicalPreservingPrinter.setup(resultNode);
-            }
-
-            configuration.getValidator().accept(resultNode, new ProblemReporter(parser.problems));
-            parser.problems.sort(PROBLEM_BY_BEGIN_POSITION);
-
             ParseResult<N> result = new ParseResult<>(resultNode, parser.problems, parser.getTokens(),
                     parser.getCommentsCollection());
-            considerInjectingSymbolResolver(result, configuration);
+
+            configuration.getPostProcessors().forEach(postProcessor ->
+                    postProcessor.process(result, configuration));
+
+            result.getProblems().sort(PROBLEM_BY_BEGIN_POSITION);
 
             return result;
         } catch (Exception e) {
@@ -531,14 +519,4 @@ public final class JavaParser {
     public static PackageDeclaration parsePackageDeclaration(String packageDeclaration) {
         return simplifiedParse(PACKAGE_DECLARATION, provider(packageDeclaration));
     }
-
-    private void considerInjectingSymbolResolver(ParseResult<?> parseResult, ParserConfiguration parserConfiguration) {
-        parserConfiguration.getSymbolResolver().ifPresent(symbolResolver ->
-                parseResult.getResult().ifPresent(result -> {
-                    if (result instanceof CompilationUnit) {
-                        ((CompilationUnit) result).setData(Node.SYMBOL_RESOLVER_KEY, symbolResolver);
-                    }
-                })
-        );
-    }
 }
diff --git a/javaparser-core/src/main/java/com/github/javaparser/ParseResult.java b/javaparser-core/src/main/java/com/github/javaparser/ParseResult.java
index 903d401ef..77180be62 100644
--- a/javaparser-core/src/main/java/com/github/javaparser/ParseResult.java
+++ b/javaparser-core/src/main/java/com/github/javaparser/ParseResult.java
@@ -21,6 +21,7 @@
 
 package com.github.javaparser;
 
+import com.github.javaparser.ast.Node;
 import com.github.javaparser.ast.comments.CommentsCollection;
 
 import java.util.List;
@@ -28,7 +29,6 @@ import java.util.Optional;
 import java.util.function.Consumer;
 
 import static com.github.javaparser.utils.Utils.EOL;
-import static java.util.Collections.singletonList;
 
 /**
  * The results given when parsing with an instance of JavaParser.
@@ -54,22 +54,6 @@ public class ParseResult<T> {
     }
 
     /**
-     * Used when parsing failed completely with an exception.
-     */
-    ParseResult(Throwable throwable) {
-        this(null, singletonList(
-                new Problem(createMessage(throwable), null, throwable)), null, null);
-    }
-
-    private static String createMessage(Throwable throwable) {
-        String message = throwable.getMessage();
-        if (message == null) {
-            return throwable.getClass().getSimpleName();
-        }
-        return message;
-    }
-
-    /**
      * @return if parsing was successful, meaning no errors of any kind were encountered.
      */
     public boolean isSuccessful() {
@@ -102,7 +86,7 @@ public class ParseResult<T> {
     /**
      * @return the complete list of tokens that were parsed, or empty if parsing failed completely.
      * @deprecated lists of tokens are now kept in every node.
-     * Calling this method is comparable to calling getResult().get().getTokenRange().get() 
+     * Calling this method is comparable to calling getResult().get().getTokenRange().get()
      */
     @Deprecated
     public Optional<List<JavaToken>> getTokens() {
@@ -134,4 +118,12 @@ public class ParseResult<T> {
         }
         return message.toString();
     }
+
+    /**
+     * A post processor that can be added to ParserConfiguration to add some processing right after parsing.
+     */
+    public interface PostProcessor {
+        void process(ParseResult<? extends Node> result, ParserConfiguration configuration);
+    }
+
 }
diff --git a/javaparser-core/src/main/java/com/github/javaparser/ParserConfiguration.java b/javaparser-core/src/main/java/com/github/javaparser/ParserConfiguration.java
index f722eca7a..05afde2fb 100644
--- a/javaparser-core/src/main/java/com/github/javaparser/ParserConfiguration.java
+++ b/javaparser-core/src/main/java/com/github/javaparser/ParserConfiguration.java
@@ -21,14 +21,18 @@
 
 package com.github.javaparser;
 
+import com.github.javaparser.ast.CompilationUnit;
+import com.github.javaparser.ast.Node;
 import com.github.javaparser.ast.validator.Java8Validator;
+import com.github.javaparser.ast.validator.ProblemReporter;
 import com.github.javaparser.ast.validator.Validator;
+import com.github.javaparser.printer.lexicalpreservation.LexicalPreservingPrinter;
 import com.github.javaparser.resolution.SymbolResolver;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Optional;
 
-import static com.github.javaparser.utils.Utils.assertNotNull;
-
 /**
  * The configuration that is used by the parser.
  * Note that this can be changed even when reusing the same JavaParser instance.
@@ -43,6 +47,34 @@ public class ParserConfiguration {
     private SymbolResolver symbolResolver = null;
     private int tabSize = 1;
     private Validator validator = new Java8Validator();
+    private final List<ParseResult.PostProcessor> postProcessors = new ArrayList<>();
+
+    public ParserConfiguration() {
+        postProcessors.add((result, configuration) -> {
+            if (configuration.isLexicalPreservationEnabled()) {
+                if (configuration.isLexicalPreservationEnabled()) {
+                    result.ifSuccessful(LexicalPreservingPrinter::setup);
+                }
+            }
+        });
+        postProcessors.add((result, configuration) -> {
+            if (configuration.isAttributeComments()) {
+                result.ifSuccessful(resultNode -> result
+                        .getCommentsCollection().ifPresent(comments ->
+                                new CommentsInserter(configuration).insertComments(resultNode, comments.copy().getComments())));
+            }
+        });
+        postProcessors.add((result, configuration) ->
+                getValidator().ifPresent(validator ->
+                        validator.accept(result.getResult().get(), new ProblemReporter(newProblem -> result.getProblems().add(newProblem)))));
+        postProcessors.add((result, configuration) -> configuration.getSymbolResolver().ifPresent(symbolResolver ->
+                result.ifSuccessful(resultNode -> {
+                    if (resultNode instanceof CompilationUnit) {
+                        resultNode.setData(Node.SYMBOL_RESOLVER_KEY, symbolResolver);
+                    }
+                })
+        ));
+    }
 
     public boolean isAttributeComments() {
         return attributeComments;
@@ -100,16 +132,16 @@ public class ParserConfiguration {
         return this;
     }
 
-    public Validator getValidator() {
-        return validator;
+    public Optional<Validator> getValidator() {
+        return Optional.of(validator);
     }
 
     /**
-     * The validator to run directly after parsing.
+     * The language level validator to run directly after parsing.
      * By default it is {@link Java8Validator}
+     * If it is null, all validation is turned off and only hard parse errors will be reported.
      */
     public ParserConfiguration setValidator(Validator validator) {
-        assertNotNull(validator);
         this.validator = validator;
         return this;
     }
@@ -142,4 +174,8 @@ public class ParserConfiguration {
         this.symbolResolver = symbolResolver;
         return this;
     }
+
+    public List<ParseResult.PostProcessor> getPostProcessors() {
+        return postProcessors;
+    }
 }
diff --git a/javaparser-core/src/main/java/com/github/javaparser/ast/validator/ProblemReporter.java b/javaparser-core/src/main/java/com/github/javaparser/ast/validator/ProblemReporter.java
index f5dc663b2..eb54810c1 100644
--- a/javaparser-core/src/main/java/com/github/javaparser/ast/validator/ProblemReporter.java
+++ b/javaparser-core/src/main/java/com/github/javaparser/ast/validator/ProblemReporter.java
@@ -4,7 +4,7 @@ import com.github.javaparser.Problem;
 import com.github.javaparser.TokenRange;
 import com.github.javaparser.ast.nodeTypes.NodeWithTokenRange;
 
-import java.util.List;
+import java.util.function.Consumer;
 
 import static com.github.javaparser.utils.CodeGenerationUtils.f;
 
@@ -12,10 +12,10 @@ import static com.github.javaparser.utils.CodeGenerationUtils.f;
  * A simple interface where validators can report found problems.
  */
 public class ProblemReporter {
-    private final List<Problem> problems;
+    private final Consumer<Problem> problemConsumer;
 
-    public ProblemReporter(List<Problem> problems) {
-        this.problems = problems;
+    public ProblemReporter(Consumer<Problem> problemConsumer) {
+        this.problemConsumer = problemConsumer;
     }
 
     /**
@@ -29,6 +29,6 @@ public class ProblemReporter {
     }
 
     public void report(TokenRange range, String message, Object... args) {
-        problems.add(new Problem(f(message, args), range, null));
+        problemConsumer.accept(new Problem(f(message, args), range, null));
     }
 }