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* published by the Free Software Foundation.
  
Oracle designates this
 
* particular file as subject to the "Classpath" exception as provided
 
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*
 
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* FITNESS FOR A PARTICULAR PURPOSE.
  
See the GNU General Public License
 
* version 2 for more details (a copy is included in the LICENSE file that
 
* accompanied this code).
 
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package java.nio.file;

import java.nio.file.spi.FileSystemProvider;
import java.net.URI;

/**
 
* This class consists exclusively of static methods that return a {@link Path}
 
* by converting a path string or {@link URI}.
 
*
 
* @since 1.7
 
*/


public final class Paths {
    
private Paths() { }

    
/**
     
* Converts a path string, or a sequence of strings that when joined form
     
* a path string, to a {@code Path}. If {@code more} does not specify any
     
* elements then the value of the {@code first} parameter is the path string
     
* to convert. If {@code more} specifies one or more elements then each
     
* non-empty string, including {@code first}, is considered to be a sequence
     
* of name elements (see {@link Path}) and is joined to form a path string.
     
* The details as to how the Strings are joined is provider specific but
     
* typically they will be joined using the {@link FileSystem#getSeparator
     
* name-separator} as the separator. For example, if the name separator is
     
* "{@code /}" and {@code getPath("/foo","bar","gus")} is invoked, then the
     
* path string {@code "/foo/bar/gus"} is converted to a {@code Path}.
     
* A {@code Path} representing an empty path is returned if {@code first}
     
* is the empty string and {@code more} does not contain any non-empty
     
* strings.
     
*
     
* <p> The {@code Path} is obtained by invoking the {@link FileSystem#getPath
     
* getPath} method of the {@link FileSystems#getDefault default} {@link
     
* FileSystem}.
     
*
     
* <p> Note that while this method is very convenient, using it will imply
     
* an assumed reference to the default {@code FileSystem} and limit the
     
* utility of the calling code. Hence it should not be used in library code
     
* intended for flexible reuse. A more flexible alternative is to use an
     
* existing {@code Path} instance as an anchor, such as:
     
* <pre>
     
*Path dir = ...
     
*Path path = dir.resolve("file");
     
* </pre>
     
*
     
* @param
   
first
     
*
          
the path string or initial part of the path string
     
* @param
   
more
     
*
          
additional strings to be joined to form the path string
     
*
     
* @return
  
the resulting {@code Path}
     
*
     
* @throws
  
InvalidPathException
     
*
          
if the path string cannot be converted to a {@code Path}
     
*
     
* @see FileSystem#getPath
     
*/

    
public static Path get(String first, String... more) {
        
return FileSystems.getDefault().getPath(first, more);
    
}

    
/**
     
* Converts the given URI to a {@link Path} object.
     
*
     
* <p> This method iterates over the {@link FileSystemProvider#installedProviders()
     
* installed} providers to locate the provider that is identified by the
     
* URI {@link URI#getScheme scheme} of the given URI. URI schemes are
     
* compared without regard to case. If the provider is found then its {@link
     
* FileSystemProvider#getPath getPath} method is invoked to convert the
     
* URI.
     
*
     
* <p> In the case of the default provider, identified by the URI scheme
     
* "file", the given URI has a non-empty path component, and undefined query
     
* and fragment components. Whether the authority component may be present
     
* is platform specific. The returned {@code Path} is associated with the
     
* {@link FileSystems#getDefault default} file system.
     
*
     
* <p> The default provider provides a similar <em>round-trip</em> guarantee
     
* to the
 
 
class. For a given {@code Path} <i>p</i> it
     
* is guaranteed that
     
* <blockquote><tt>
     
* Paths.get(</tt><i>p</i><tt>.{@link Path#toUri() toUri}()).equals(</tt>
     
* <i>p</i><tt>.{@link Path#toAbsolutePath() toAbsolutePath}())</tt>
     
* </blockquote>
     
* so long as the original {@code Path}, the {@code URI}, and the new {@code
     
* Path} are all created in (possibly different invocations of) the same
     
* Java virtual machine. Whether other providers make any guarantees is
     
* provider specific and therefore unspecified.
     
*
     
* @param
   
uri
     
*
          
the URI to convert
     
*
     
* @return
  
the resulting {@code Path}
     
*
     
* @throws
  
IllegalArgumentException
     
*
          
if preconditions on the {@code uri} parameter do not hold. The
     
*
          
format of the URI is provider specific.
     
* @throws
  
FileSystemNotFoundException
     
*
          
The file system, identified by the URI, does not exist and
     
*
          
cannot be created automatically, or the provider identified by
     
*
          
the URI's scheme component is not installed
     
* @throws
  
SecurityException
     
*
          
if a security manager is installed and it denies an unspecified
     
*
          
permission to access the file system
     
*/

    
public static Path get(URI uri) {
        
String scheme =
  
uri.getScheme();
        
if (scheme == null)
            
throw new IllegalArgumentException("Missing scheme");

        
// check for default provider to avoid loading of installed providers
        
if (scheme.equalsIgnoreCase("file"))
            
return FileSystems.getDefault().provider().getPath(uri);

        
// try to find provider
        
for (FileSystemProvider provider: FileSystemProvider.installedProviders()) {
            
if (provider.getScheme().equalsIgnoreCase(scheme)) {
                
return provider.getPath(uri);
            
}
        
}

        
throw new FileSystemNotFoundException("Provider \"" + scheme + "\" not installed");
    
}
}