[R-Help] Remove DateStream.copy to avoid misuse

Change-Id: I301f7343ea6ffa5575b02d0a7cb80234d6036531
diff --git a/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/DataStream.java b/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/DataStream.java
index e479a75..cfbe769 100644
--- a/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/DataStream.java
+++ b/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/DataStream.java
@@ -39,7 +39,7 @@
 public final class DataStream implements AutoCloseable {
 	
 	
-	private static final ThreadLocal<DataStream> INSTANCES= new ThreadLocal<DataStream>() {
+	private static final ThreadLocal<DataStream> INSTANCES= new ThreadLocal<>() {
 		
 		@Override
 		protected DataStream initialValue() {
@@ -62,14 +62,6 @@
 		return io;
 	}
 	
-	public static void copy(final InputStream in, final OutputStream out) throws IOException {
-		final byte[] buffer= INSTANCES.get().ba;
-		int n;
-		while ((n = in.read(buffer, 0, buffer.length)) != -1) {
-			out.write(buffer, 0, n);
-		}
-	}
-	
 	
 	public static long decodeLong(final byte[] ba) {
 		return (((long) (ba[0] & 0xff) << 56) |
diff --git a/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/SerUtil.java b/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/SerUtil.java
index 7358757..aebde9e 100644
--- a/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/SerUtil.java
+++ b/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/internal/rhelp/core/SerUtil.java
@@ -18,7 +18,6 @@
 import java.io.BufferedOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.OutputStream;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
@@ -154,8 +153,8 @@
 		try {
 			final Path directory= getIndexDirectoryChecked(rEnvConfig);
 			final Path newFile= directory.resolve(RHELP_SER_FILE + ".new"); //$NON-NLS-1$
-			Files.deleteIfExists(newFile);
 			
+			Files.deleteIfExists(newFile);
 			try (final DataStream out= DataStream.get(new BufferedOutputStream(
 					Files.newOutputStream(newFile, StandardOpenOption.CREATE_NEW) ))) {
 				save(help, out, COMPRESS);
@@ -186,12 +185,8 @@
 		try {
 			final Path directory= getIndexDirectoryChecked(rEnvConfig);
 			final Path newFile= directory.resolve(RHELP_SER_FILE + ".new"); //$NON-NLS-1$
-			Files.deleteIfExists(newFile);
 			
-			try (final OutputStream out= new BufferedOutputStream(
-					Files.newOutputStream(newFile, StandardOpenOption.CREATE_NEW) )) {
-				DataStream.copy(in, out);
-			}
+			Files.copy(in, newFile, StandardCopyOption.REPLACE_EXISTING);
 			
 			synchronized (controller.getFileLock()) {
 				if (!controller.shouldSave()) {