de.schlichtherle.truezip.fs.spi.FsDriverService Maven / Gradle / Ivy
/*
* Copyright (C) 2005-2015 Schlichtherle IT Services.
* All rights reserved. Use is subject to license terms.
*/
package de.schlichtherle.truezip.fs.spi;
import de.schlichtherle.truezip.fs.FsDriver;
import de.schlichtherle.truezip.fs.FsDriverProvider;
import de.schlichtherle.truezip.fs.FsScheme;
import de.schlichtherle.truezip.fs.sl.FsDriverLocator;
import de.schlichtherle.truezip.util.HashMaps;
import de.schlichtherle.truezip.util.ServiceLocator;
import de.schlichtherle.truezip.util.SuffixSet;
import java.net.URISyntaxException;
import java.util.*;
/**
* An abstract locatable service for a map of file system schemes to
* file system drivers.
* Implementations of this abstract class are subject to service location
* by the class {@link FsDriverLocator}.
*
* Implementations must be thread-safe.
*
* @author Christian Schlichtherle
*/
public abstract class FsDriverService implements FsDriverProvider {
/**
* Returns a string representation of this object for debugging and logging
* purposes.
*/
@Override
public String toString() {
return getClass().getName();
}
/**
* A static factory method for an unmodifiable driver map which is
* constructed from the given configuration.
* This method is intended to be used by implementations of this class
* for convenient creation of the map to return by their {@link #get()}
* method.
*
* @param config an array of key-value pair arrays.
* The first element of each inner array must either be a
* {@link FsScheme file system scheme}, an object {@code o} which
* can get converted to a set of file name suffixes by calling
* new {@link SuffixSet#SuffixSet(String) SuffixSet}(o.toString())
* or a {@link Collection collection} of these.
* The second element of each inner array must either be a
* {@link FsDriver file system driver instance}, a
* {@link Class file system driver class}, a
* {@link String fully qualified name of a file system driver class},
* or {@code null}.
* @return The file system driver map created from the given configuration.
* @throws NullPointerException if a required configuration element is
* {@code null}.
* @throws IllegalArgumentException if any other parameter precondition
* does not hold.
* @see SuffixSet Syntax contraints for suffix lists.
*/
public static Map newMap(final Object[][] config) {
final Map drivers = new HashMap(
HashMaps.initialCapacity(config.length) * 2); // heuristics
for (final Object[] param : config) {
final Collection schemes = toSchemes(param[0]);
final FsDriver newDriver = ServiceLocator
.promote(param[1], FsDriver.class);
if (schemes.isEmpty())
throw new IllegalArgumentException("No file system schemes for " + newDriver);
for (final FsScheme scheme : schemes) {
final FsDriver oldDriver = drivers.put(scheme, newDriver);
if (null != oldDriver && null != newDriver
&& oldDriver.getPriority() > newDriver.getPriority())
drivers.put(scheme, oldDriver);
}
}
return Collections.unmodifiableMap(drivers);
}
private static Collection toSchemes(final Object o) {
final Collection set = new TreeSet();
try {
if (o instanceof Collection)
for (final Object p : (Collection) o)
if (p instanceof FsScheme)
set.add((FsScheme) p);
else
for (String q : new SuffixSet(p.toString()))
set.add(new FsScheme(q));
else if (o instanceof FsScheme)
set.add((FsScheme) o);
else
for (final String p : new SuffixSet(o.toString()))
set.add(new FsScheme(p));
} catch (URISyntaxException ex) {
throw new IllegalArgumentException(ex);
}
return set;
}
}