.diff

diff --git a/core/src/main/java/org/jruby/RubyEncoding.java b/core/src/main/java/org/jruby/RubyEncoding.java
index f327459c89..daa8b21acd 100755
--- a/core/src/main/java/org/jruby/RubyEncoding.java
+++ b/core/src/main/java/org/jruby/RubyEncoding.java
@@ -58,6 +58,8 @@ import org.jruby.util.StringSupport;
 import org.jruby.util.io.EncodingUtils;
 import org.jruby.util.unsafe.UnsafeHolder;
 
+import static org.jruby.util.io.ChannelHelper.clearBuffer;
+
 @JRubyClass(name="Encoding")
 public class RubyEncoding extends RubyObject implements Constantizable {
     public static final Charset UTF8 = Charset.forName("UTF-8");
@@ -301,10 +303,8 @@ public class RubyEncoding extends RubyObject implements Constantizable {
         }
 
         public final ByteBuffer encode(String str) {
-            ByteBuffer buf = byteBuffer;
-            CharBuffer cbuf = charBuffer;
-            buf.clear();
-            cbuf.clear();
+            ByteBuffer buf = clearBuffer(byteBuffer);
+            CharBuffer cbuf = clearBuffer(charBuffer);
             cbuf.put(str);
             cbuf.flip();
             encoder.encode(cbuf, buf, true);
@@ -314,10 +314,8 @@ public class RubyEncoding extends RubyObject implements Constantizable {
         }
 
         public final ByteBuffer encode(CharSequence str) {
-            ByteBuffer buf = byteBuffer;
-            CharBuffer cbuf = charBuffer;
-            buf.clear();
-            cbuf.clear();
+            ByteBuffer buf = clearBuffer(byteBuffer);
+            CharBuffer cbuf = clearBuffer(charBuffer);
             // NOTE: doesn't matter is we toString here in terms of speed
             // ... so we "safe" some space at least by not copy-ing char[]
             for (int i = 0; i < str.length(); i++) cbuf.put(str.charAt(i));
@@ -329,10 +327,8 @@ public class RubyEncoding extends RubyObject implements Constantizable {
         }
 
         public final CharBuffer decode(byte[] bytes, int start, int length) {
-            CharBuffer cbuf = charBuffer;
-            ByteBuffer buf = byteBuffer;
-            cbuf.clear();
-            buf.clear();
+            ByteBuffer buf = clearBuffer(byteBuffer);
+            CharBuffer cbuf = clearBuffer(charBuffer);
             buf.put(bytes, start, length);
             buf.flip();
             decoder.decode(buf, cbuf, true);
diff --git a/core/src/main/java/org/jruby/RubyIO.java b/core/src/main/java/org/jruby/RubyIO.java
index d99135396f..07150f2223 100644
--- a/core/src/main/java/org/jruby/RubyIO.java
+++ b/core/src/main/java/org/jruby/RubyIO.java
@@ -4445,7 +4445,7 @@ public class RubyIO extends RubyObject implements IOEncodable, Closeable, Flusha
 
             buffer.flip();
             to.write(buffer);
-            buffer.clear();
+            clearBuffer(buffer);
 
             transferred += n;
             if (length > 0) {
diff --git a/core/src/main/java/org/jruby/embed/io/ReaderInputStream.java b/core/src/main/java/org/jruby/embed/io/ReaderInputStream.java
index 6713e7a726..542b9dbf77 100644
--- a/core/src/main/java/org/jruby/embed/io/ReaderInputStream.java
+++ b/core/src/main/java/org/jruby/embed/io/ReaderInputStream.java
@@ -42,6 +42,8 @@ import java.nio.charset.CodingErrorAction;
 import java.util.ArrayList;
 import java.util.List;
 
+import static org.jruby.util.io.ChannelHelper.clearBuffer;
+
 /**
  * A ReaderInputStream converts java.io.Reader to java.io.InputStream. The
  * ReaderInputStream reads data in a given Reader object into its internal buffer
@@ -105,7 +107,7 @@ public class ReaderInputStream extends InputStream {
         ByteBuffer bbuf = ByteBuffer.allocate(DEFAULT_BYTE_BUFFER_SIZE);
         List<byte[]> list = new ArrayList<byte[]>();
         while (true) {
-            cbuf.clear();
+            clearBuffer(cbuf);
             int size = reader.read(cbuf);
             if (size <= 0) {
                 break;
@@ -122,7 +124,7 @@ public class ReaderInputStream extends InputStream {
                     eof = true;
                 } else if (cr.isOverflow()) {
                     appendBytes(list, bbuf);
-                    bbuf.clear();
+                    clearBuffer(bbuf);
                 }
             }
         }
diff --git a/core/src/main/java/org/jruby/embed/io/WriterOutputStream.java b/core/src/main/java/org/jruby/embed/io/WriterOutputStream.java
index a51eff5963..0af8775bbb 100644
--- a/core/src/main/java/org/jruby/embed/io/WriterOutputStream.java
+++ b/core/src/main/java/org/jruby/embed/io/WriterOutputStream.java
@@ -40,6 +40,8 @@ import java.nio.charset.CharsetDecoder;
 import java.nio.charset.CoderResult;
 import java.nio.charset.CodingErrorAction;
 
+import static org.jruby.util.io.ChannelHelper.clearBuffer;
+
 /**
  * A WriterOutputStream converts java.io.Writer to java.io.OutputStream.
  *
@@ -203,7 +205,7 @@ public class WriterOutputStream extends OutputStream {
 
     private void byte2char(ByteBuffer bytes, CharBuffer chars) throws IOException {
         decoder.reset();
-        chars.clear();
+        clearBuffer(chars);
         CoderResult result = decoder.decode(bytes, chars, true);
         if (result.isError() || result.isOverflow()) {
             throw new IOException(result.toString());
diff --git a/core/src/main/java/org/jruby/util/ShellLauncher.java b/core/src/main/java/org/jruby/util/ShellLauncher.java
index a715c9364b..3bed80baf8 100644
--- a/core/src/main/java/org/jruby/util/ShellLauncher.java
+++ b/core/src/main/java/org/jruby/util/ShellLauncher.java
@@ -29,6 +29,7 @@
 package org.jruby.util;
 
 import static java.lang.System.out;
+import static org.jruby.util.io.ChannelHelper.clearBuffer;
 
 import java.io.File;
 import java.io.FileInputStream;
@@ -1484,14 +1485,14 @@ public class ShellLauncher {
         public void run() {
             runtime.getCurrentContext().setEventHooksEnabled(false);
             ByteBuffer buf = ByteBuffer.allocateDirect(1024);
-            buf.clear();
+            clearBuffer(buf);
             try {
                 while (!quit && inChannel.isOpen() && outChannel.isOpen()) {
                     int read = inChannel.read(buf);
                     if (read == -1) break;
                     buf.flip();
                     outChannel.write(buf);
-                    buf.clear();
+                    clearBuffer(buf);
                 }
             } catch (Exception e) {
             } finally {
diff --git a/core/src/main/java/org/jruby/util/io/ChannelHelper.java b/core/src/main/java/org/jruby/util/io/ChannelHelper.java
index 185f2fac1a..555b688dcd 100644
--- a/core/src/main/java/org/jruby/util/io/ChannelHelper.java
+++ b/core/src/main/java/org/jruby/util/io/ChannelHelper.java
@@ -19,6 +19,7 @@ import java.io.FilterOutputStream;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.lang.reflect.Field;
+import java.nio.Buffer;
 import java.nio.channels.Channels;
 import java.nio.channels.ReadableByteChannel;
 import java.nio.channels.WritableByteChannel;
@@ -177,6 +178,16 @@ public abstract class ChannelHelper {
         return filteredStream;
     }
 
+    /**
+     * Call the Buffer.clear method by casting to Buffer, so it will continue to work on Java 8.
+     *
+     * @param buffer the buffer on which to call clear
+     * @return the original buffer reference
+     */
+    public static <T extends Buffer> T clearBuffer(T buffer) {
+        return (T) buffer.clear();
+    }
+
     private static OutputStream unwrapDripStream(OutputStream stream) {
         if (isDripSwitchable(stream)) {
             try {
diff --git a/core/src/main/java/org/jruby/util/io/ChannelStream.java b/core/src/main/java/org/jruby/util/io/ChannelStream.java
index 19198c76d0..ff0ffd5f1d 100644
--- a/core/src/main/java/org/jruby/util/io/ChannelStream.java
+++ b/core/src/main/java/org/jruby/util/io/ChannelStream.java
@@ -57,6 +57,8 @@ import org.jruby.util.ResourceException;
 import org.jruby.util.log.Logger;
 import org.jruby.util.log.LoggerFactory;
 
+import static org.jruby.util.io.ChannelHelper.clearBuffer;
+
 /**
  * This file implements a seekable IO file.
  */
@@ -212,7 +214,7 @@ public class ChannelStream implements Stream, Finalizable {
 
     @Override
     public final int refillBuffer() throws IOException {
-        buffer.clear();
+        clearBuffer(buffer);
         int n = ((ReadableByteChannel) descriptor.getChannel()).read(buffer);
         buffer.flip();
         return n;
@@ -261,7 +263,7 @@ public class ChannelStream implements Stream, Finalizable {
                         // terminate and advance buffer when we find our char
                         buf.append(bytes, offset, i - offset);
                         if (i >= max) {
-                            buffer.clear();
+                            clearBuffer(buffer);
                         } else {
                             buffer.position(i + 1);
                         }
@@ -699,7 +701,7 @@ public class ChannelStream implements Stream, Finalizable {
         if(n != len) {
             // TODO: check the return value here
         }
-        buffer.clear();
+        clearBuffer(buffer);
     }
 
     /**
@@ -735,7 +737,7 @@ public class ChannelStream implements Stream, Finalizable {
             buffer.compact();
             return false;
         }
-        buffer.clear();
+        clearBuffer(buffer);
         return true;
     }
 
@@ -804,7 +806,7 @@ public class ChannelStream implements Stream, Finalizable {
             if (reading) {
                 // for SEEK_CUR, need to adjust for buffered data
                 adj = buffer.remaining();
-                buffer.clear();
+                clearBuffer(buffer);
                 buffer.flip();
             } else {
                 flushWrite();
@@ -846,7 +848,7 @@ public class ChannelStream implements Stream, Finalizable {
     private void ensureRead() throws IOException, BadDescriptorException {
         if (reading) return;
         flushWrite();
-        buffer.clear();
+        clearBuffer(buffer);
         buffer.flip();
         reading = true;
     }
@@ -868,7 +870,7 @@ public class ChannelStream implements Stream, Finalizable {
         } else {
             // libc flushes writes on any read from the actual file, so we flush here
             flushWrite();
-            buffer.clear();
+            clearBuffer(buffer);
             buffer.flip();
             reading = true;
         }
@@ -882,7 +884,7 @@ public class ChannelStream implements Stream, Finalizable {
             }
         }
         // FIXME: Clearing read buffer here...is this appropriate?
-        buffer.clear();
+        clearBuffer(buffer);
         reading = false;
     }
 
@@ -1439,7 +1441,7 @@ public class ChannelStream implements Stream, Finalizable {
         flushWrite();
 
         // reset buffer
-        buffer.clear();
+        clearBuffer(buffer);
         if (reading) {
             buffer.flip();
         }