tree of SourceFragments

src/main/java/spoon/experimental/modelobs/ChangeCollector.java

@@ -123,7 +123,12 @@ CtRole getScannedRole() {
 		}
 	}
 
-	private void onChange(CtElement currentElement, CtRole role) {
+	/**
+	 * Called whenever anything changes in the spoon model
+	 * @param currentElement the modified element
+	 * @param role the modified attribute of that element
+	 */
+	protected void onChange(CtElement currentElement, CtRole role) {
 		Set<CtRole> roles = elementToChangeRole.get(currentElement);
 		if (roles == null) {
 			roles = new HashSet<>();

src/main/java/spoon/experimental/modelobs/SourceFragmentsTreeCreatingChangeCollector.java

@@ -0,0 +1,39 @@
+/**
+ * Copyright (C) 2006-2017 INRIA and contributors
+ * Spoon - http://spoon.gforge.inria.fr/
+ *
+ * This software is governed by the CeCILL-C License under French law and
+ * abiding by the rules of distribution of free software. You can use, modify
+ * and/or redistribute the software under the terms of the CeCILL-C license as
+ * circulated by CEA, CNRS and INRIA at http://www.cecill.info.
+ *
+ * This program 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 CeCILL-C License for more details.
+ *
+ * The fact that you are presently reading this means that you have had
+ * knowledge of the CeCILL-C license and that you accept its terms.
+ */
+package spoon.experimental.modelobs;
+
+import spoon.reflect.cu.CompilationUnit;
+import spoon.reflect.declaration.CtElement;
+import spoon.reflect.path.CtRole;
+import spoon.reflect.visitor.printer.change.SourceFragment;
+
+/**
+ * Listens on changes  on the spoon model and remembers them
+ * It builds a tree of {@link SourceFragment}s of {@link CompilationUnit} of the modified element
+ * lazily before the element is changed
+ */
+public class SourceFragmentsTreeCreatingChangeCollector extends ChangeCollector {
+	@Override
+	protected void onChange(CtElement currentElement, CtRole role) {
+		CompilationUnit cu = currentElement.getPosition().getCompilationUnit();
+		if (cu != null) {
+			//build a tree of SourceFragments of compilation unit of the modified element before the first change
+			cu.getRootSourceFragment();
+		}
+		super.onChange(currentElement, role);
+	}
+}

src/main/java/spoon/reflect/cu/CompilationUnit.java

@@ -20,6 +20,8 @@
 import spoon.reflect.declaration.CtModule;
 import spoon.reflect.declaration.CtPackage;
 import spoon.reflect.declaration.CtType;
+import spoon.reflect.visitor.printer.change.SourceFragment;
+import spoon.reflect.declaration.CtElement;
 import spoon.reflect.declaration.CtImport;
 
 import java.io.File;
@@ -55,6 +57,16 @@ enum UNIT_TYPE {
 	 */
 	void setFile(File file);
 
+	/**
+	 * @return array of offsets in the origin source file, where occurs line separator
+	 */
+	int[] getLineSeparatorPositions();
+
+	/**
+	 * @param lineSeparatorPositions array of offsets in the origin source file, where occurs line separator
+	 */
+	void setLineSeparatorPositions(int[] lineSeparatorPositions);
+
 	/**
 	 * Gets all binary (.class) files that corresponds to this compilation unit
 	 * and have been created by calling
@@ -149,4 +161,18 @@ enum UNIT_TYPE {
 	 */
 	void setImports(Collection<CtImport> imports);
 
+	/**
+	 * @return root {@link SourceFragment} of the tree of all the source fragments of origin source code
+	 * Note: this method creates tree of {@link SourceFragment}s ... it can be a lot of instances
+	 * If the tree of {@link SourceFragment}s is needed then it MUST be created
+	 * BEFORE the Spoon model of this {@link CompilationUnit} is changed.
+	 * Otherwise there might be missing some {@link SourceFragment}s when {@link CtElement}s are deleted
+	 */
+	SourceFragment getRootSourceFragment();
+
+	/**
+	 * @param element the {@link CtElement} whose origin source code is needed
+	 * @return {@link SourceFragment} which mirrors the origin source code of the `element` or null.
+	 */
+	SourceFragment getSourceFragment(CtElement element);
 }

src/main/java/spoon/reflect/cu/SourcePosition.java

@@ -83,16 +83,4 @@ public interface SourcePosition extends Serializable {
 	 * Gets the index at which the position starts in the source file.
 	 */
 	int getSourceStart();
-
-	/**
-	 * @return {@link SourcePosition} of next element in the origin source code.
-	 * If there is no one, then it returns null. It never returns {@link NoSourcePosition}
-	 */
-	SourcePosition getNextSibling();
-
-	/**
-	 * @return {@link SourcePosition} of first child element in the origin source code.
-	 * If there is no one, then it returns null. It never returns {@link NoSourcePosition}
-	 */
-	SourcePosition getFirstChild();
 }

src/main/java/spoon/reflect/cu/position/NoSourcePosition.java

@@ -73,14 +73,4 @@ public int getSourceStart() {
 	public String toString() {
 		return "(unknown file)";
 	}
-
-	@Override
-	public SourcePosition getFirstChild() {
-		return null;
-	}
-
-	@Override
-	public SourcePosition getNextSibling() {
-		return null;
-	}
 }

src/main/java/spoon/reflect/visitor/printer/change/ChangesAwareDefaultJavaPrettyPrinter.java

@@ -20,9 +20,7 @@
 import java.lang.reflect.Method;
 import java.lang.reflect.Proxy;
 import java.util.ArrayDeque;
-import java.util.Collections;
 import java.util.Deque;
-import java.util.List;
 import java.util.function.Predicate;
 
 import spoon.SpoonException;
@@ -103,30 +101,36 @@ protected void onTokenWriterWrite(String tokenWriterMethodName, String token, Pr
 	}
 
 	private class SourceFragmentContext {
-		final List<SourceFragment> fragments;
-		int currentFragmentIdx = -1;
+		private SourceFragment currentFragment;
+		private CtElement element;
 
-		SourceFragmentContext(List<SourceFragment> fragments) {
+		SourceFragmentContext(CtElement element, SourceFragment rootFragment) {
 			super();
-			this.fragments = fragments;
+			this.element = element;
+			this.currentFragment = rootFragment;
 		}
 
 		SourceFragmentContext() {
-			this.fragments = Collections.emptyList();
-			currentFragmentIdx = 0;
+			currentFragment = null;
+		}
+
+		SourceFragment getNextFragment() {
+			if (currentFragment != null) {
+				return currentFragment.getNextFragmentOfSameElement();
+			}
+			return null;
 		}
 
 		/**
 		 * Called when next fragment is going to be printed
 		 */
 		void nextFragment() {
-			currentFragmentIdx++;
-			if (currentFragmentIdx < fragments.size()) {
-				SourceFragment fragment = fragments.get(currentFragmentIdx);
-				if (fragment.isModified() == false) {
+			currentFragment = getNextFragment();
+			if (currentFragment != null) {
+				if (currentFragment.isModified() == false) {
 					//we are going to print not modified fragment
 					//print origin sources of this fragment directly
-					mutableTokenWriter.getPrinterHelper().directPrint(fragment.toString());
+					mutableTokenWriter.getPrinterHelper().directPrint(currentFragment.toString());
 					mutableTokenWriter.setMuted(true);
 				} else {
 					//we are printing modified fragment. Let it print normally
@@ -135,9 +139,8 @@ void nextFragment() {
 			}
 		}
 
-		boolean testFagmentDescriptor(int fragmentIdx, Predicate<FragmentDescriptor> predicate) {
-			if (fragmentIdx < fragments.size()) {
-				SourceFragment sourceFragment = fragments.get(fragmentIdx);
+		boolean testFagmentDescriptor(SourceFragment sourceFragment, Predicate<FragmentDescriptor> predicate) {
+			if (sourceFragment != null) {
 				if (sourceFragment.fragmentDescriptor != null) {
 					return predicate.test(sourceFragment.fragmentDescriptor);
 				}
@@ -146,20 +149,20 @@ boolean testFagmentDescriptor(int fragmentIdx, Predicate<FragmentDescriptor> pre
 		}
 
 		void onTokenWriterToken(String tokenWriterMethodName, String token, PrintAction printAction) throws Exception {
-			if (testFagmentDescriptor(currentFragmentIdx + 1, fd -> fd.isTriggeredByToken(true, tokenWriterMethodName, token))) {
+			if (testFagmentDescriptor(getNextFragment(), fd -> fd.isTriggeredByToken(true, tokenWriterMethodName, token))) {
 				//yes, the next fragment should be activated before printAction
 				nextFragment();
 			}
 			//run the print action, which we are listening for
 			printAction.run();
-			if (testFagmentDescriptor(currentFragmentIdx, fd -> fd.isTriggeredByToken(false, tokenWriterMethodName, token))) {
+			if (testFagmentDescriptor(currentFragment, fd -> fd.isTriggeredByToken(false, tokenWriterMethodName, token))) {
 				//yes, the next fragment should be activated before printAction
 				nextFragment();
 			}
 		}
 
 		void onScanRole(CtRole role, PrintAction printAction) {
-			if (testFagmentDescriptor(currentFragmentIdx + 1, fd -> fd.isStartedByScanRole(role))) {
+			if (testFagmentDescriptor(getNextFragment(), fd -> fd.isStartedByScanRole(role))) {
 				//yes, the next fragment should be activated before printAction
 				nextFragment();
 			}
@@ -173,7 +176,6 @@ void onScanRole(CtRole role, PrintAction printAction) {
 			}
 //			{
 //				//check if current fragment has to be finished after this action
-//				SourceFragment currentFragment = fragments.get(currentFragmentIdx);
 //				if (currentFragment.fragmentDescriptor.isFinishedByScanRole(role)) {
 //					nextFragment();
 //				}
@@ -208,16 +210,16 @@ private void scanInternal(CtElement element) {
 		}
 		//it is not muted yet, so some this element or any sibling was modified
 		//detect SourceFragments of element and whether they are modified or not
-		List<SourceFragment> fragments = SourcePositionUtils.getSourceFragmentsOfElement(changeCollector, element);
-		if (fragments.isEmpty()) {
+		SourceFragment rootFragmentOfElement = SourcePositionUtils.getSourceFragmentsOfElement(changeCollector, element);
+		if (rootFragmentOfElement == null) {
 			//we have no origin sources. Use normal printing
 			sourceFragmentContextStack.push(EMPTY_FRAGMENT_CONTEXT);
 			super.scan(element);
 			sourceFragmentContextStack.pop();
 			return;
 		}
 		try {
-			SourceFragmentContext sfx = new SourceFragmentContext(fragments);
+			SourceFragmentContext sfx = new SourceFragmentContext(element, rootFragmentOfElement);
 			sourceFragmentContextStack.push(sfx);
 			//move to the first fragment - and handle printing of modified or not modified content
 			sfx.nextFragment();