/*
 * Copyright 2013 Julien Viet
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.asciidoc.intellij;

import com.intellij.lang.Language;
import com.intellij.openapi.fileTypes.SingleLazyInstanceSyntaxHighlighterFactory;
import com.intellij.openapi.fileTypes.SyntaxHighlighter;
import com.intellij.openapi.fileTypes.SyntaxHighlighterFactory;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.psi.FileViewProvider;
import com.intellij.psi.PsiManager;
import org.asciidoc.intellij.lexer.AsciiDocHighlighter;
import org.jetbrains.annotations.NotNull;

/** @author Julien Viet */
public class AsciiDocLanguage extends Language {

  public static final Language INSTANCE = new AsciiDocLanguage();

  /** . */
  public static final String LANGUAGE_NAME = "AsciiDoc";

  private AsciiDocLanguage() {
    super(LANGUAGE_NAME);
    SyntaxHighlighterFactory.LANGUAGE_FACTORY.addExplicitExtension(this, new SingleLazyInstanceSyntaxHighlighterFactory() {
      @NotNull
      protected SyntaxHighlighter createHighlighter() {
        return new AsciiDocHighlighter();
      }
    });
  }

  public static final boolean isAsciiDocFile(@NotNull Project project, @NotNull VirtualFile file) {
    if (!file.isFile()) {
      return false;
    }
    final FileViewProvider provider = PsiManager.getInstance(project).findViewProvider(file);
    return provider != null && provider.getBaseLanguage().isKindOf(INSTANCE);
  }
}

/*
 * Copyright 2013 Julien Viet
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.asciidoc.intellij;

import com.intellij.lang.Language;
import com.intellij.openapi.fileTypes.SingleLazyInstanceSyntaxHighlighterFactory;
import com.intellij.openapi.fileTypes.SyntaxHighlighter;
import com.intellij.openapi.fileTypes.SyntaxHighlighterFactory;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.psi.FileViewProvider;
import com.intellij.psi.PsiManager;
import org.asciidoc.intellij.lexer.AsciiDocHighlighter;
import org.jetbrains.annotations.NotNull;

/** @author Julien Viet */
public class AsciiDocLanguage extends Language {

  public static final Language INSTANCE = new AsciiDocLanguage();

  /** . */
  public static final String LANGUAGE_NAME = "AsciiDoc";

  private AsciiDocLanguage() {
    super(LANGUAGE_NAME);
    SyntaxHighlighterFactory.LANGUAGE_FACTORY.addExplicitExtension(this, new SingleLazyInstanceSyntaxHighlighterFactory() {
      @NotNull
      protected SyntaxHighlighter createHighlighter() {
        return new AsciiDocHighlighter();
      }
    });
  }

  public static final boolean isAsciiDocFile(@NotNull Project project, @NotNull VirtualFile file) {
    if (file.isDirectory() || !file.exists()) {
      return false;
    }
    final FileViewProvider provider = PsiManager.getInstance(project).findViewProvider(file);
    return provider != null && provider.getBaseLanguage().isKindOf(INSTANCE);
  }
}

Update AsciiDocLanguage.java