How to use

ExtractClassRefactoring

in

org.eclipse.jdt.internal.corext.refactoring.structure

@Override
public Refactoring createRefactoring(JavaRefactoringDescriptor descriptor, RefactoringStatus status) throws CoreException {
  if (!(descriptor instanceof ExtractClassDescriptor)) {
    status.addFatalError(RefactoringCoreMessages.ExtractClassContribution_error_unknown_descriptor);
    return null;
  }
  return new ExtractClassRefactoring((ExtractClassDescriptor) descriptor);
}

@Override
public Change createChange(IProgressMonitor pm) throws CoreException, OperationCanceledException {
  pm.beginTask(RefactoringCoreMessages.ExtractClassRefactoring_progress_create_change, 10);
  try {
    ICompilationUnit typeCU= fDescriptor.getType().getCompilationUnit();
    IPackageFragmentRoot packageRoot= (IPackageFragmentRoot) typeCU.getAncestor(IJavaElement.PACKAGE_FRAGMENT_ROOT);
    ArrayList<Change> changes= new ArrayList<>();
    changes.addAll(createParameterObject(fParameterObjectFactory, packageRoot));
    fChangeManager.manage(typeCU, fBaseCURewrite.createChange(true, pm));
    changes.addAll(Arrays.asList(fChangeManager.getAllChanges()));
    String project= fDescriptor.getType().getJavaProject().getElementName();
    fDescriptor.setProject(project);
    fDescriptor.setDescription(getName());
    fDescriptor.setComment(createComment());
    DynamicValidationRefactoringChange change= new DynamicValidationRefactoringChange(fDescriptor, RefactoringCoreMessages.ExtractClassRefactoring_change_name, changes
        .toArray(new Change[changes.size()]));
    return change;
  } finally {
    pm.done();
  }
}

private boolean isCreateField(FieldInfo fi) {
  return getField(fi.name).isCreateField();
}

ParameterInfo pi= getFieldInfo(name.getIdentifier()).pi;
boolean writeAccess= ASTResolving.isWriteAccess(name);
if (writeAccess && fDescriptor.isCreateGetterSetter()) {
  boolean useSuper= parent.getNodeType() == ASTNode.SUPER_FIELD_ACCESS;
  Expression qualifier= getQualifier(parent);
  ASTNode replaceNode= getReplacementNode(parent, useSuper, qualifier);
  Expression assignedValue= getAssignedValue(pof, parameterName, javaProject, status, rewrite, pi, useSuper, name.resolveTypeBinding(), qualifier, replaceNode, typeRoot);
  if (assignedValue == null) {
    status.addError(RefactoringCoreMessages.ExtractClassRefactoring_error_unable_to_convert_node, JavaStatusContext.create(typeRoot, replaceNode));
    NullLiteral marker= qualifier == null ? null : ast.newNullLiteral();
    Expression access= pof.createFieldWriteAccess(pi, parameterName, ast, javaProject, assignedValue, useSuper, marker);
    replaceMarker(rewrite, qualifier, access, marker);
    rewrite.replace(replaceNode, access, writeGroup);

TextEditGroup removeFieldGroup= fBaseCURewrite.createGroupDescription(RefactoringCoreMessages.ExtractClassRefactoring_group_remove_field);
FieldDeclaration lastField= null;
initializeDeclaration(typeNode);
for (Iterator<FieldInfo> iter= fVariables.values().iterator(); iter.hasNext();) {
  FieldInfo pi= iter.next();
  if (isCreateField(pi)) {
    VariableDeclarationFragment vdf= pi.declaration;
    FieldDeclaration parent= (FieldDeclaration) vdf.getParent();
    removeNode(vdf, removeFieldGroup, fBaseCURewrite);
    if (listRewrite.getRewrittenList().size() == 0) {
      removeNode(parent, removeFieldGroup, fBaseCURewrite);
FieldDeclaration fieldDeclaration= createParameterObjectField(pof, typeNode, modifier);
ListRewrite bodyDeclList= rewrite.getListRewrite(typeNode, TypeDeclaration.BODY_DECLARATIONS_PROPERTY);
if (lastField != null)

private ParameterObjectFactory initializeFactory() {
  ParameterObjectFactory pof= new ParameterObjectFactory();
  pof.setClassName(fDescriptor.getClassName());
  pof.setPackage(fDescriptor.getPackage());
  pof.setEnclosingType(fDescriptor.getType().getFullyQualifiedName('.'));
  pof.setCreateGetter(fDescriptor.isCreateGetterSetter());
  pof.setCreateSetter(fDescriptor.isCreateGetterSetter());
  List<ParameterInfo> variables= new ArrayList<>();
  for (Iterator<FieldInfo> iterator= fVariables.values().iterator(); iterator.hasNext();) {
    FieldInfo info= iterator.next();
    boolean createField= isCreateField(info);
    info.pi.setCreateField(createField);
    if (createField) {
      Field field= getField(info.name);
      info.pi.setNewName(field.getNewFieldName());
    }
    variables.add(info.pi);
  }
  pof.setVariables(variables);
  return pof;
}

private void initializeDeclaration(TypeDeclaration node) {
  FieldDeclaration[] fields= node.getFields();
  for (int i= 0; i < fields.length; i++) {
    FieldDeclaration fieldDeclaration= fields[i];
    List<VariableDeclarationFragment> fragments= fieldDeclaration.fragments();
    for (Iterator<VariableDeclarationFragment> iterator= fragments.iterator(); iterator.hasNext();) {
      VariableDeclarationFragment vdf= iterator.next();
      FieldInfo fieldInfo= getFieldInfo(vdf.getName().getIdentifier());
      if (fieldInfo != null) {
        Assert.isNotNull(vdf);
        fieldInfo.declaration= vdf;
        fieldInfo.pi.setOldBinding(vdf.resolveBinding());
      }
    }
  }
}

ParameterInfo pi= getFieldInfo(name.getIdentifier()).pi;
boolean writeAccess= ASTResolving.isWriteAccess(name);
if (writeAccess && fDescriptor.isCreateGetterSetter()) {
  boolean useSuper= parent.getNodeType() == ASTNode.SUPER_FIELD_ACCESS;
  Expression qualifier= getQualifier(parent);
  ASTNode replaceNode= getReplacementNode(parent, useSuper, qualifier);
  Expression assignedValue= getAssignedValue(pof, parameterName, javaProject, status, rewrite, pi, useSuper, name.resolveTypeBinding(), qualifier, replaceNode, typeRoot);
  if (assignedValue == null) {
    status.addError(RefactoringCoreMessages.ExtractClassRefactoring_error_unable_to_convert_node, JavaStatusContext.create(typeRoot, replaceNode));
    NullLiteral marker= qualifier == null ? null : ast.newNullLiteral();
    Expression access= pof.createFieldWriteAccess(pi, parameterName, ast, javaProject, assignedValue, useSuper, marker);
    replaceMarker(rewrite, qualifier, access, marker);
    rewrite.replace(replaceNode, access, writeGroup);

TextEditGroup removeFieldGroup= fBaseCURewrite.createGroupDescription(RefactoringCoreMessages.ExtractClassRefactoring_group_remove_field);
FieldDeclaration lastField= null;
initializeDeclaration(typeNode);
for (Iterator<FieldInfo> iter= fVariables.values().iterator(); iter.hasNext();) {
  FieldInfo pi= iter.next();
  if (isCreateField(pi)) {
    VariableDeclarationFragment vdf= pi.declaration;
    FieldDeclaration parent= (FieldDeclaration) vdf.getParent();
    removeNode(vdf, removeFieldGroup, fBaseCURewrite);
    if (listRewrite.getRewrittenList().size() == 0) {
      removeNode(parent, removeFieldGroup, fBaseCURewrite);
FieldDeclaration fieldDeclaration= createParameterObjectField(pof, typeNode, modifier);
ListRewrite bodyDeclList= rewrite.getListRewrite(typeNode, TypeDeclaration.BODY_DECLARATIONS_PROPERTY);
if (lastField != null)

private ParameterObjectFactory initializeFactory() {
  ParameterObjectFactory pof= new ParameterObjectFactory();
  pof.setClassName(fDescriptor.getClassName());
  pof.setPackage(fDescriptor.getPackage());
  pof.setEnclosingType(fDescriptor.getType().getFullyQualifiedName('.'));
  pof.setCreateGetter(fDescriptor.isCreateGetterSetter());
  pof.setCreateSetter(fDescriptor.isCreateGetterSetter());
  List<ParameterInfo> variables= new ArrayList<>();
  for (Iterator<FieldInfo> iterator= fVariables.values().iterator(); iterator.hasNext();) {
    FieldInfo info= iterator.next();
    boolean createField= isCreateField(info);
    info.pi.setCreateField(createField);
    if (createField) {
      Field field= getField(info.name);
      info.pi.setNewName(field.getNewFieldName());
    }
    variables.add(info.pi);
  }
  pof.setVariables(variables);
  return pof;
}

private void initializeDeclaration(TypeDeclaration node) {
  FieldDeclaration[] fields= node.getFields();
  for (int i= 0; i < fields.length; i++) {
    FieldDeclaration fieldDeclaration= fields[i];
    List<VariableDeclarationFragment> fragments= fieldDeclaration.fragments();
    for (Iterator<VariableDeclarationFragment> iterator= fragments.iterator(); iterator.hasNext();) {
      VariableDeclarationFragment vdf= iterator.next();
      FieldInfo fieldInfo= getFieldInfo(vdf.getName().getIdentifier());
      if (fieldInfo != null) {
        Assert.isNotNull(vdf);
        fieldInfo.declaration= vdf;
        fieldInfo.pi.setOldBinding(vdf.resolveBinding());
      }
    }
  }
}

@Override
public Change createChange(IProgressMonitor pm) throws CoreException, OperationCanceledException {
  pm.beginTask(RefactoringCoreMessages.ExtractClassRefactoring_progress_create_change, 10);
  try {
    ICompilationUnit typeCU= fDescriptor.getType().getCompilationUnit();
    IPackageFragmentRoot packageRoot= (IPackageFragmentRoot) typeCU.getAncestor(IJavaElement.PACKAGE_FRAGMENT_ROOT);
    ArrayList<Change> changes= new ArrayList<>();
    changes.addAll(createParameterObject(fParameterObjectFactory, packageRoot));
    fChangeManager.manage(typeCU, fBaseCURewrite.createChange(true, pm));
    changes.addAll(Arrays.asList(fChangeManager.getAllChanges()));
    String project= fDescriptor.getType().getJavaProject().getElementName();
    fDescriptor.setProject(project);
    fDescriptor.setDescription(getName());
    fDescriptor.setComment(createComment());
    DynamicValidationRefactoringChange change= new DynamicValidationRefactoringChange(fDescriptor, RefactoringCoreMessages.ExtractClassRefactoring_change_name, changes
        .toArray(new Change[changes.size()]));
    return change;
  } finally {
    pm.done();
  }
}

@Override
public Refactoring createRefactoring(JavaRefactoringDescriptor descriptor, RefactoringStatus status) throws CoreException {
  if (!(descriptor instanceof ExtractClassDescriptor)) {
    status.addFatalError(RefactoringCoreMessages.ExtractClassContribution_error_unknown_descriptor);
    return null;
  }
  return new ExtractClassRefactoring((ExtractClassDescriptor) descriptor);
}

private Expression handleSimpleNameAssignment(ASTNode replaceNode, ParameterObjectFactory pof, String parameterName, AST ast, IJavaProject javaProject, boolean useSuper) {
  if (replaceNode instanceof Assignment) {
    Assignment assignment= (Assignment) replaceNode;
    Expression rightHandSide= assignment.getRightHandSide();
    if (rightHandSide.getNodeType() == ASTNode.SIMPLE_NAME) {
      SimpleName sn= (SimpleName) rightHandSide;
      IVariableBinding binding= ASTNodes.getVariableBinding(sn);
      if (binding != null && binding.isField()) {
        if (fDescriptor.getType().getFullyQualifiedName().equals(binding.getDeclaringClass().getQualifiedName())) {
          FieldInfo fieldInfo= getFieldInfo(binding.getName());
          if (fieldInfo != null && binding == fieldInfo.pi.getOldBinding()) {
            return pof.createFieldReadAccess(fieldInfo.pi, parameterName, ast, javaProject, useSuper, null);
          }
        }
      }
    }
  }
  return null;
}

private boolean isCreateField(FieldInfo fi) {
  return getField(fi.name).isCreateField();
}

public static void startExtractClassRefactoring(IType type, Shell shell) {
  ExtractClassDescriptor descriptor= RefactoringSignatureDescriptorFactory.createExtractClassDescriptor();
  descriptor.setType(type);
  ExtractClassRefactoring refactoring= new ExtractClassRefactoring(descriptor);
  ExtractClassWizard wizard= new ExtractClassWizard(descriptor, refactoring);
  new RefactoringStarter().activate(wizard, shell, RefactoringMessages.OpenRefactoringWizardAction_refactoring, RefactoringSaveHelper.SAVE_REFACTORING);
}

private Expression handleSimpleNameAssignment(ASTNode replaceNode, ParameterObjectFactory pof, String parameterName, AST ast, IJavaProject javaProject, boolean useSuper) {
  if (replaceNode instanceof Assignment) {
    Assignment assignment= (Assignment) replaceNode;
    Expression rightHandSide= assignment.getRightHandSide();
    if (rightHandSide.getNodeType() == ASTNode.SIMPLE_NAME) {
      SimpleName sn= (SimpleName) rightHandSide;
      IVariableBinding binding= ASTNodes.getVariableBinding(sn);
      if (binding != null && binding.isField()) {
        if (fDescriptor.getType().getFullyQualifiedName().equals(binding.getDeclaringClass().getQualifiedName())) {
          FieldInfo fieldInfo= getFieldInfo(binding.getName());
          if (fieldInfo != null && binding == fieldInfo.pi.getOldBinding()) {
            return pof.createFieldReadAccess(fieldInfo.pi, parameterName, ast, javaProject, useSuper, null);
          }
        }
      }
    }
  }
  return null;
}

public static void startExtractClassRefactoring(IType type, Shell shell) {
  ExtractClassDescriptor descriptor= RefactoringSignatureDescriptorFactory.createExtractClassDescriptor();
  descriptor.setType(type);
  ExtractClassRefactoring refactoring= new ExtractClassRefactoring(descriptor);
  ExtractClassWizard wizard= new ExtractClassWizard(descriptor, refactoring);
  new RefactoringStarter().activate(wizard, shell, RefactoringMessages.OpenRefactoringWizardAction_refactoring, RefactoringSaveHelper.SAVE_REFACTORING);
}