Fixed URI encoding with special characters

Fixes issue Upplication#105 by running the uri through URLEncoder.encode and then
converting allowable characters :, / and [space] back.

src/main/java/com/upplication/s3fs/S3Path.java

@@ -1,22 +1,28 @@
 package com.upplication.s3fs;
 
-import com.google.common.base.*;
-import com.google.common.collect.ImmutableList;
-import com.google.common.collect.Lists;
-import com.upplication.s3fs.attribute.S3BasicFileAttributes;
+import static com.google.common.collect.Iterables.concat;
+import static java.lang.String.format;
 
 import java.io.File;
 import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.net.URI;
 import java.net.URL;
 import java.net.URLDecoder;
-import java.nio.file.*;
+import java.net.URLEncoder;
+import java.nio.file.LinkOption;
+import java.nio.file.Path;
+import java.nio.file.WatchEvent;
+import java.nio.file.WatchKey;
+import java.nio.file.WatchService;
 import java.util.Iterator;
 import java.util.List;
 
-import static com.google.common.collect.Iterables.*;
-import static java.lang.String.format;
+import com.google.common.base.Preconditions;
+import com.google.common.base.Splitter;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Lists;
+import com.upplication.s3fs.attribute.S3BasicFileAttributes;
 
 public class S3Path implements Path {
 
@@ -583,10 +589,17 @@ public int hashCode() {
      * @return String
      */
     private String encode(String uri) {
-        // remove special case URI starting with //
-        uri = uri.replace("//", "/");
-        uri = uri.replaceAll(" ", "%20");
-        return uri;
+        try {
+            // URL encode all characters, but then convert known allowed characters back
+            return URLEncoder.encode(uri, "UTF-8")
+            .replace("%3A", ":")
+            .replace("%2F", "/")
+            .replace("+", "%20");
+        } catch (UnsupportedEncodingException e) {
+            // This should never happen unless there is something
+            // fundamentally broken with the running JVM.
+            throw new RuntimeException(e);
+        }
     }
 
     /**

src/test/java/com/upplication/s3fs/Path/ToUriTest.java

@@ -1,25 +1,25 @@
 package com.upplication.s3fs.Path;
 
-import com.google.common.collect.ImmutableMap;
-import com.upplication.s3fs.S3FileSystem;
-import com.upplication.s3fs.S3FileSystemProvider;
-import com.upplication.s3fs.S3Path;
-import com.upplication.s3fs.S3UnitTestBase;
-import com.upplication.s3fs.util.S3EndpointConstant;
-import org.junit.Before;
-import org.junit.Test;
+import static com.upplication.s3fs.AmazonS3Factory.ACCESS_KEY;
+import static com.upplication.s3fs.AmazonS3Factory.SECRET_KEY;
+import static com.upplication.s3fs.util.S3EndpointConstant.S3_GLOBAL_URI_TEST;
+import static org.junit.Assert.assertEquals;
 
 import java.io.IOException;
 import java.net.URI;
 import java.nio.file.FileSystem;
 import java.nio.file.Path;
 import java.util.Map;
 
-import static com.upplication.s3fs.AmazonS3Factory.ACCESS_KEY;
-import static com.upplication.s3fs.AmazonS3Factory.SECRET_KEY;
-import static com.upplication.s3fs.util.S3EndpointConstant.*;
+import org.junit.Before;
+import org.junit.Test;
 
-import static org.junit.Assert.assertEquals;
+import com.google.common.collect.ImmutableMap;
+import com.upplication.s3fs.S3FileSystem;
+import com.upplication.s3fs.S3FileSystemProvider;
+import com.upplication.s3fs.S3Path;
+import com.upplication.s3fs.S3UnitTestBase;
+import com.upplication.s3fs.util.S3EndpointConstant;
 
 public class ToUriTest extends S3UnitTestBase {
 
@@ -50,6 +50,25 @@ public void toUri() {
         assertEquals(path, pathActual);
     }
 
+    @Test
+    public void toUriSpecialChars() {
+        Path path = getPath("/bucket/([fol! @#$%der])");
+        URI uri = path.toUri();
+
+        // the scheme is s3
+        assertEquals("s3", uri.getScheme());
+
+        // could get the correct fileSystem
+        S3FileSystem fs =  s3fsProvider.getFileSystem(uri);
+        // the host is the endpoint specified in fileSystem
+        assertEquals(fs.getEndpoint(), uri.getHost());
+
+        // bucket name as first path
+        Path pathActual = fs.provider().getPath(uri);
+
+        assertEquals(path, pathActual);
+    }
+
     @Test
     public void toUriWithEndSlash() {
         S3Path s3Path = getPath("/bucket/folder/");