SystemLibraryManager refactor - to separate package and sdk library functionality

compiler/java/com/google/dart/compiler/SystemLibraryManager.java

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 package com.google.dart.compiler;
 
-import java.io.BufferedInputStream;
 import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.io.InputStream;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.HashMap;
-import java.util.HashSet;
 import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Properties;
 
 
 /**
  * Manages the collection of {@link SystemLibrary}s.
  */
 public class SystemLibraryManager {
 
   public static class NotADartShortUriException extends RuntimeException {
 
     public NotADartShortUriException(String uriString) {
@@ skipping 12 matching lines @@
   public static final String DEFAULT_PLATFORM = "any";
   public static final File DEFAULT_SDK_PATH = new File(System.getProperty(
       "com.google.dart.sdk", "../"));
   
   public static final File DEFAULT_PACKAGE_ROOT = new File("packages");
   public static final List<File> DEFAULT_PACKAGE_ROOTS = Arrays.asList(new File[] {DEFAULT_PACKAGE_ROOT});
 
   public static final String PACKAGE_SCHEME = "package";
   public static final String PACKAGE_SCHEME_SPEC = "package:";
 
-  private static final String DART_SCHEME = "dart";
-  private static final String DART_SCHEME_SPEC = "dart:";
-  private static final String IMPORT_CONFIG = "import_%s.config";
+  public static final String DART_SCHEME = "dart";
+  public static final String DART_SCHEME_SPEC = "dart:";
+
 
   /**
    * Answer <code>true</code> if the string is a dart spec
    */
   public static boolean isDartSpec(String spec) {
     return spec != null && spec.startsWith(DART_SCHEME_SPEC);
   }
 
   /**
    * Answer <code>true</code> if the specified URI has a "dart" scheme
    */
   public static boolean isDartUri(URI uri) {
     return uri != null && DART_SCHEME.equals(uri.getScheme());
   }
 
   /**
    * Answer <code>true</code> if the string is a package spec
    */
   public static boolean isPackageSpec(String spec) {
     return spec != null && spec.startsWith(PACKAGE_SCHEME_SPEC);
   }
 
   /**
    * Answer <code>true</code> if the specified URI has a "package" scheme
    */
   public static boolean isPackageUri(URI uri) {
     return uri != null && PACKAGE_SCHEME.equals(uri.getScheme());
   }
 
-  private HashMap<String, String> expansionMap;
-  private Map<String, SystemLibrary> hostMap;
-  private final File sdkLibPath;
-  private final URI sdkLibPathUri;
-  private final String platformName;
- 
+  private static SdkLibraryManager SDK_LIBRARY_MANAGER;
+  
   private List<File> packageRoots = new ArrayList<File>();
   private List<URI> packageRootsUri = new ArrayList<URI>(); 
 
-  private Map<URI, URI> longToShortUriMap;
-
-  private List<SystemLibrary> libraries;
-
   public SystemLibraryManager() {
     this(DEFAULT_SDK_PATH, DEFAULT_PLATFORM);
   }
 
   public SystemLibraryManager(File sdkPath, String platformName) {
-    this.sdkLibPath = new File(sdkPath, "lib").getAbsoluteFile();
-    this.sdkLibPathUri = sdkLibPath.toURI();
-    this.platformName = platformName;
-    setLibraries(getDefaultLibraries());
-    setPackageRoots(DEFAULT_PACKAGE_ROOTS);
+    if (SDK_LIBRARY_MANAGER == null){
+      SDK_LIBRARY_MANAGER = new SdkLibraryManager(sdkPath, platformName);
+    }
   }
 
 
   /**
    * Expand a relative or short URI (e.g. "dart:html") which is implementation independent to its
    * full URI (e.g. "dart://html/com/google/dart/htmllib/html.dart").
    *
    * @param uri the relative URI
    * @return the expanded URI
    *  or the original URI if it could not be expanded
    *  or null if the uri is of the form "dart:<libname>" but does not correspond to a system library
    */
   public URI expandRelativeDartUri(URI uri) throws AssertionError {
     if (isDartUri(uri)) {
-      String host = uri.getHost();
-      if (host == null) {
-        String spec = uri.getSchemeSpecificPart();
-        String replacement = expansionMap.get(spec);
-        if (replacement != null) {
-          try {
-            uri = new URI(DART_SCHEME + ":" + replacement);
-          } catch (URISyntaxException e) {
-            throw new AssertionError();
-          }
-        } else {
-          return null;
-        }
-      }
+      return SDK_LIBRARY_MANAGER.expandRelativeDartUri(uri);
     } 
     if (isPackageUri(uri)){
       String host = uri.getHost();
       if (host == null) {
         String spec = uri.getSchemeSpecificPart();
         if (!spec.startsWith("//")){
           try {
             if (spec.startsWith("/")){
               // TODO(keertip): fix to handle spaces
               uri = new URI(PACKAGE_SCHEME + ":/" + spec);
             } else {
               uri = new URI(PACKAGE_SCHEME + "://" + spec);
             } 
           } catch (URISyntaxException e) {
             throw new AssertionError();
           }
         }       
       }
     }
     return uri;
   }
 
-  /**
-   * Answer a collection of all bundled library URL specs (e.g. "dart:html").
-   *
-   * @return a collection of specs (not <code>null</code>, contains no <code>null</code>s)
-   */
-  public Collection<String> getAllLibrarySpecs() {
-    Collection<String> result = new ArrayList<String>(libraries.size());
-    for (SystemLibrary lib : libraries) {
-      result.add("dart:" + lib.getShortName());
-    }
-    return result;
-  }
-  
-  protected InputStream getImportConfigStream() {
-    File file = new File(new File(sdkLibPath, "config"),
-                         String.format(IMPORT_CONFIG, platformName));
-    if (!file.exists()) {
-      throw new InternalCompilerException("Failed to find " + file.toString()
-                                          + ".  Is dart-sdk path correct?");
-    }
-    try {
-      return new BufferedInputStream(new FileInputStream(file));
-    } catch (FileNotFoundException e) {
-      throw new InternalCompilerException("Failed to open " + file);
-    }
-  }
+ 
   
   /**
    * Given an absolute file URI (e.g. "file:/some/install/directory/dart-sdk/lib/core/bool.dart"),
    *  answer the corresponding dart: URI (e.g. "dart://core/bool.dart") for that file URI,
    *  or <code>null</code> if the file URI does not map to a dart: URI 
    * @param fileUri the file URI
    * @return the dart URI or <code>null</code>
    */
   public URI getRelativeUri(URI fileUri) {
     // TODO (danrubel): does not convert dart: libraries outside the dart-sdk/lib directory
     if (fileUri == null || !fileUri.getScheme().equals("file")) {
       return null;
     }
-    URI relativeUri = sdkLibPathUri.relativize(fileUri);
-    if (relativeUri.getScheme() == null) {
-      try {
-        return new URI(null, null, "dart://" + relativeUri.getPath(), null, null);
-      } catch (URISyntaxException e) {
-        //$FALL-THROUGH$
-      }
+   
+    URI relativeUri = SDK_LIBRARY_MANAGER.getRelativeUri(fileUri);
+    if (relativeUri != null){
+      return relativeUri;
     }
     
     for (URI rootUri : packageRootsUri){
       relativeUri = rootUri.relativize(fileUri);
         if (relativeUri.getScheme() == null) {
           try {
             return new URI(null, null, "package://" + relativeUri.getPath(), null, null);
           } catch (URISyntaxException e) {
         //$FALL-THROUGH$
         }
@@ skipping 24 matching lines @@
       return packageRootsUri.get(0).resolve(relPath);
     }
    return null; 
   }
 
   /**
    * Answer the original "dart:<libname>" URI for the specified resolved URI or <code>null</code> if
    * it does not map to a short URI.
    */
   public URI getShortUri(URI uri) {
-    URI shortUri = longToShortUriMap.get(uri);
+    URI shortUri = SDK_LIBRARY_MANAGER.getShortUri(uri);
     if (shortUri != null){
       return shortUri;
     }
     shortUri = getRelativeUri(uri);
     if (shortUri != null){
       try {
         return new URI(null, null, shortUri.getScheme() + ":" +  shortUri.getHost() + shortUri.getPath(),null, null);
       } catch (URISyntaxException e) {
       }
     }
@@ skipping 17 matching lines @@
   
   
   public List<File> getPackageRoots(){
     return packageRoots;
   }
   
   
   public void setPackageRoots(List<File> roots){
     if (roots == null || roots.isEmpty()){
       this.packageRoots = DEFAULT_PACKAGE_ROOTS;
-    } else {
+    } else { 
       packageRoots.clear();
       for (File file : roots){   
         packageRoots.add(file.getAbsoluteFile());
-      }
+      }   
     }
     packageRootsUri.clear();
     for (File file : roots){
       packageRootsUri.add(file.toURI());
-    }   
+    }
   }
   
   /**
    * Translate the URI from dart://[host]/[pathToLib] (e.g. dart://html/html.dart)
    * to a "file:" URI (e.g. "file:/some/install/directory/html.dart")
    *
    * @param uri the original URI
    * @return the translated URI, which may be <code>null</code> and may not exist
    * @exception RuntimeException if the URI is a "dart" scheme,
    *     but does not map to a defined system library
    */
   public URI translateDartUri(URI uri) {
     if (isDartUri(uri)) {
-      String host = uri.getHost();
-      SystemLibrary library = hostMap.get(host);
-      if (library != null) {
-        return library.translateUri(uri);
-      }
-      if (host != null) {
-        return new File(getSdkLibPath(), host).toURI().resolve("." + uri.getPath());
-      }
-      throw new RuntimeException("No system library defined for " + uri);
+     return SDK_LIBRARY_MANAGER.translateDartUri(uri);
     } 
     if (isPackageUri(uri)){   
       URI fileUri;
       for (URI rootUri : packageRootsUri){
         fileUri = getResolvedPackageUri(uri, rootUri);
         File file  = new File(fileUri);
         if (file.exists()){
           return file.toURI();
         }
       }
@@ skipping 28 matching lines @@
     // so use uri.getAuthority to resolve
     // package://third_party/dart_lang/lib/unittest/unittest.dart
     if (uri.getHost() != null){
       fileUri =  packageRootUri.resolve(uri.getHost() + uri.getPath());
     } else {
       fileUri = packageRootUri.resolve(uri.getAuthority() + uri.getPath());
     }
     return fileUri;
   }
 
+  /**
+   * Answer a collection of all bundled library URL specs (e.g. "dart:html").
+   *
+   * @return a collection of specs (not <code>null</code>, contains no <code>null</code>s)
+   */
+  public Collection<String> getAllLibrarySpecs() {
+    return SDK_LIBRARY_MANAGER.getAllLibrarySpecs();
+  }
+  
+  protected SystemLibrary[] getDefaultLibraries() {
+    return SDK_LIBRARY_MANAGER.getDefaultLibraries();
+    
+  }
+  
   public File getSdkLibPath() {
-    return sdkLibPath;
+    return SDK_LIBRARY_MANAGER.getSdkLibPath();
   }
-
-  /**
-   * Scan the directory returned by {@link #getLibrariesDir()} looking for libraries of the form
-   * libraries/<name>/<name>_<platform>.dart and libraries/<name>/<name>.dart where <platform> is
-   * the value initialized in the {@link SystemLibraryManager}.
-   */
-  protected SystemLibrary[] getDefaultLibraries() {
-    libraries = new ArrayList<SystemLibrary>();
-    longToShortUriMap = new HashMap<URI, URI>();
-
-    // Cycle through the import.config, extracting explicit mappings and searching directories
-    URI base = this.sdkLibPathUri;
-    Properties importConfig = getImportConfig();
-    HashSet<String> explicitShortNames = new HashSet<String>();
-    for (Entry<Object, Object> entry : importConfig.entrySet()) {
-      String shortName = ((String) entry.getKey()).trim();
-      String path = ((String) entry.getValue()).trim();
-
-      File file;
-      try {
-        file = new File(base.resolve(new URI(null, null, path, null, null)).normalize());
-      } catch (URISyntaxException e) {
-        continue;
-      }
-      if (!file.exists()) {
-        throw new InternalCompilerException("Can't find system library dart:" + shortName
-                                            + " at " + file);
-      }
-
-      // If the shortName ends with ":" then search the associated directory for libraries
-
-      if (shortName.endsWith(":")) {
-        if (!file.isDirectory()) {
-          continue;
-        }
-        for (File child : file.listFiles()) {
-          String host = child.getName();
-          // Do not overwrite explicit shortName to dart file mappings
-          if (explicitShortNames.contains(shortName + host)) {
-            continue;
-          }
-          if (!child.isDirectory()) {
-            continue;
-          }
-          File dartFile = new File(child, child.getName() + ".dart");
-          if (!dartFile.isFile()) {
-            // addLib() will throw an exception. In this case, we are just scanning
-            // for libraries and don't want the error to be fatal.
-            continue;
-          }
-          addLib(shortName, host, host, child, dartFile.getName());
-        }
-      } else {
-        // Otherwise treat the entry as an explicit shortName to dart file mapping
-        int index = shortName.indexOf(':');
-        if (index == -1) {
-          continue;
-        }
-        explicitShortNames.add(shortName);
-        String scheme = shortName.substring(0, index + 1);
-        String name = shortName.substring(index + 1);
-        String host = file.getParentFile().getName();
-        addLib(scheme, host, name, file.getParentFile(), file.getName());
-      }
-    }
-    return libraries.toArray(new SystemLibrary[libraries.size()]);
-  }
-
-  /**
-   * Read the import.config content and return it as a collection of key/value pairs
-   */
-  protected Properties getImportConfig() {
-    Properties importConfig = new Properties();
-    InputStream stream = getImportConfigStream();
-    try {
-      importConfig.load(stream);
-    } catch (IOException ignored) {
-    } finally {
-      try {
-        stream.close();
-      } catch (IOException ignored) {
-      }
-    }
-    return importConfig;
-  }
-
-  private boolean addLib(String scheme, String host, String name, File dir, String libFileName)
-      throws AssertionError {
-    File libFile = new File(dir, libFileName);
-    if (!libFile.isFile()) {
-      throw new InternalCompilerException("Error mapping dart:" + host + ", path "
-          + libFile.getAbsolutePath() + " is not a file.");
-    }
-    SystemLibrary lib = new SystemLibrary(name, host, libFileName, dir);
-    libraries.add(lib);
-    String libSpec = scheme + name;
-    URI libUri;
-    URI expandedUri;
-    try {
-      libUri = new URI(libSpec);
-      expandedUri = new URI("dart:" + "//" + host + "/" + libFileName);
-    } catch (URISyntaxException e) {
-      throw new AssertionError(e);
-    }
-    URI resolvedUri = lib.translateUri(expandedUri);
-    longToShortUriMap.put(resolvedUri, libUri);
-    longToShortUriMap.put(expandedUri, libUri);
-    return true;
-  }
-
-  /**
-   * Register system libraries for the "dart:" protocol such that dart:[shortLibName] (e.g.
-   * "dart:html") will automatically be expanded to dart://[host]/[pathToLib] (e.g.
-   * dart://html/html.dart)
-   */
-  private void setLibraries(SystemLibrary[] newLibraries) {
-    libraries = new ArrayList<SystemLibrary>();
-    hostMap = new HashMap<String, SystemLibrary>();
-    expansionMap = new HashMap<String, String>();
-    for (SystemLibrary library : newLibraries) {
-      String host = library.getHost();
-      SystemLibrary existingLib = hostMap.get(host);
-      if (existingLib != null) {
-        libraries.remove(existingLib);
-      }
-      libraries.add(library);
-      hostMap.put(host, library);
-      expansionMap.put(library.getShortName(),
-          "//" + host + "/" + library.getPathToLib());
-    }
-  }
+  
+  
+  
 }