Without Fast-Path

Author: mkarg

src/java.base/share/classes/sun/nio/cs/StreamDecoder.java

@@ -49,7 +49,6 @@ public class StreamDecoder extends Reader {
     private static final int MIN_BYTE_BUFFER_SIZE = 32;
     private static final int DEFAULT_BYTE_BUFFER_SIZE = 8192;
 
-    private volatile boolean opened;
     private volatile boolean closed;
 
     private void ensureOpen() throws IOException {
@@ -117,7 +116,6 @@ public String getEncoding() {
     }
 
     public int read() throws IOException {
-        opened = true;
         return read0();
     }
 
@@ -151,7 +149,6 @@ private int read0() throws IOException {
 
     public int read(char[] cbuf, int offset, int length) throws IOException {
         synchronized (lock) {
-            opened = true;
             int off = offset;
             int len = length;
 
@@ -195,21 +192,41 @@ public int read(char[] cbuf, int offset, int length) throws IOException {
         }
     }
 
+    private static CharBuffer ensureFree(CharBuffer cb, int minFree) {
+        return cb.remaining() < minFree ? CharBuffer.allocate(cb.position() + minFree).put(cb.flip()) : cb;
+    }
+
     @Override
     public String readAllAsString() throws IOException {
         synchronized (lock) {
             ensureOpen();
-            final String s = (in == null || opened) ? super.readAllAsString() : new String(in.readAllBytes(), cs);
-            opened = true;
-            return s;
+
+            int estimateSize = (haveLeftoverChar ? 1 : 0) + (int) Math.ceil((bb.remaining() + in.available()) * decoder.maxCharsPerByte());
+            int initialSize = Math.max(estimateSize, DEFAULT_BYTE_BUFFER_SIZE);
+            CharBuffer cb = CharBuffer.allocate(initialSize);
+
+            if (haveLeftoverChar) {
+                cb.put(leftoverChar);
+                haveLeftoverChar = false;
+            }
+
+            while (bb.hasRemaining()) {
+                CoderResult cr = decoder.decode(bb, cb, false);
+                if (cr.isError()) cr.throwException();
+                if (cr.isOverflow()) cb = ensureFree(cb, bb.remaining());
+            }
+
+            ByteBuffer bbuf = ByteBuffer.wrap(in.readAllBytes());
+            while (bbuf.hasRemaining()) {
+                CoderResult cr = decoder.decode(bbuf, cb, false);
+                if (cr.isError()) cr.throwException();
+                if (cr.isOverflow()) cb = ensureFree(cb, bbuf.remaining());
+            }
+
+            return cb.flip().toString();
         }
     }
-/*
-    @Override
-    public String readAllAsString() throws IOException {
-        throw new RuntimeException();
-    }
-*/
+
     public boolean ready() throws IOException {
         synchronized (lock) {
             ensureOpen();