Adding JMCR-Stable version

[Benchmarks_CSolver.git] / JMCR-Stable / real-world application / derby-10.3.2.1 / java / engine / org / apache / derby / iapi / services / io / InputStreamUtil.java

diff --git a/JMCR-Stable/real-world application/derby-10.3.2.1/java/engine/org/apache/derby/iapi/services/io/InputStreamUtil.java b/JMCR-Stable/real-world application/derby-10.3.2.1/java/engine/org/apache/derby/iapi/services/io/InputStreamUtil.java
new file mode 100644 (file)
index 0000000..3d00e08
--- /dev/null
+++ b/JMCR-Stable/real-world application/derby-10.3.2.1/java/engine/org/apache/derby/iapi/services/io/InputStreamUtil.java
@@ -0,0 +1,123 @@
+/*\r
+\r
+   Derby - Class org.apache.derby.iapi.services.io.InputStreamUtil\r
+\r
+   Licensed to the Apache Software Foundation (ASF) under one or more\r
+   contributor license agreements.  See the NOTICE file distributed with\r
+   this work for additional information regarding copyright ownership.\r
+   The ASF licenses this file to you under the Apache License, Version 2.0\r
+   (the "License"); you may not use this file except in compliance with\r
+   the License.  You may obtain a copy of the License at\r
+\r
+      http://www.apache.org/licenses/LICENSE-2.0\r
+\r
+   Unless required by applicable law or agreed to in writing, software\r
+   distributed under the License is distributed on an "AS IS" BASIS,\r
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
+   See the License for the specific language governing permissions and\r
+   limitations under the License.\r
+\r
+ */\r
+\r
+package org.apache.derby.iapi.services.io;\r
+\r
+import java.io.*;\r
+\r
+/**\r
+       Utility methods for InputStream that are stand-ins for\r
+       a small subset of DataInput methods. This avoids pushing\r
+       a DataInputStream just to get this functionality.\r
+*/\r
+public final class InputStreamUtil {\r
+\r
+       /**\r
+               Read an unsigned byte from an InputStream, throwing an EOFException\r
+               if the end of the input is reached.\r
+\r
+               @exception IOException if an I/O error occurs.\r
+               @exception EOFException if the end of the stream is reached\r
+\r
+               @see DataInput#readUnsignedByte\r
+       \r
+       */\r
+       public static int readUnsignedByte(InputStream in) throws IOException {\r
+               int b = in.read();\r
+               if (b < 0)\r
+                       throw new EOFException();\r
+\r
+               return b;\r
+       }\r
+\r
+       /**\r
+               Read a number of bytes into an array.\r
+\r
+               @exception IOException if an I/O error occurs.\r
+               @exception EOFException if the end of the stream is reached\r
+\r
+               @see DataInput#readFully\r
+\r
+       */\r
+       public static void readFully(InputStream in, byte b[],\r
+                                 int offset,\r
+                                 int len) throws IOException\r
+       {\r
+               do {\r
+                       int bytesRead = in.read(b, offset, len);\r
+                       if (bytesRead < 0)\r
+                               throw new EOFException();\r
+                       len -= bytesRead;\r
+                       offset += bytesRead;\r
+               } while (len != 0);\r
+       }\r
+\r
+\r
+       /**\r
+               Read a number of bytes into an array.\r
+        Keep reading in a loop until len bytes are read or EOF is reached or\r
+        an exception is thrown. Return the number of bytes read.\r
+        (InputStream.read(byte[],int,int) does not guarantee to read len bytes\r
+         even if it can do so without reaching EOF or raising an exception.)\r
+\r
+               @exception IOException if an I/O error occurs.\r
+       */\r
+       public static int readLoop(InputStream in,\r
+                                byte b[],\r
+                                int offset,\r
+                                int len)\r
+        throws IOException\r
+       {\r
+        int firstOffset = offset;\r
+               do {\r
+                       int bytesRead = in.read(b, offset, len);\r
+                       if (bytesRead <= 0)\r
+                break;\r
+                       len -= bytesRead;\r
+                       offset += bytesRead;\r
+               } while (len != 0);\r
+        return offset - firstOffset;\r
+       }\r
+\r
+\r
+       /**\r
+               Skip a number of bytes in the stream. Note that this version takes and returns\r
+               a long instead of the int used by skipBytes.\r
+\r
+               @exception IOException if an I/O error occurs.\r
+               @exception EOFException if the end of the stream is reached\r
+\r
+               @see DataInput#skipBytes\r
+       */\r
+       public static long skipBytes(InputStream in, long n) throws IOException {\r
+\r
+               while (n > 0) {\r
+                       //System.out.println(" skip n = " + n);\r
+                       long delta = in.skip(n);\r
+                       //System.out.println(" skipped = " + delta);\r
+                       if (delta < 0)\r
+                               throw new EOFException();\r
+                       n -= delta;\r
+               }\r
+\r
+               return n;\r
+       }\r
+}\r