Low-level InputStream test w/mock

git-svn-id: https://svn.apache.org/repos/asf/lucene/java/trunk@150003 13f79535-47bb-0310-9956-ffa450edef68

src/test/org/apache/lucene/index/MockInputStream.java

@@ -0,0 +1,40 @@
+package org.apache.lucene.index;
+
+import org.apache.lucene.store.InputStream;
+
+import java.io.IOException;
+
+public class MockInputStream extends InputStream {
+    private byte[] buffer;
+    private int pointer = 0;
+
+    public MockInputStream(byte[] bytes) {
+        buffer = bytes;
+        length = bytes.length;
+    }
+
+    protected void readInternal(byte[] dest, int destOffset, int len)
+            throws IOException {
+        int remainder = len;
+        int start = pointer;
+        while (remainder != 0) {
+//          int bufferNumber = start / buffer.length;
+          int bufferOffset = start % buffer.length;
+          int bytesInBuffer = buffer.length - bufferOffset;
+          int bytesToCopy = bytesInBuffer >= remainder ? remainder : bytesInBuffer;
+          System.arraycopy(buffer, bufferOffset, dest, destOffset, bytesToCopy);
+          destOffset += bytesToCopy;
+          start += bytesToCopy;
+          remainder -= bytesToCopy;
+        }
+        pointer += len;
+    }
+
+    public void close() throws IOException {
+        // ignore
+    }
+
+    protected void seekInternal(long pos) throws IOException {
+        pointer = (int) pos;
+    }
+}

src/test/org/apache/lucene/index/TestInputStream.java

@@ -0,0 +1,21 @@
+package org.apache.lucene.index;
+
+import junit.framework.TestCase;
+import org.apache.lucene.store.InputStream;
+
+import java.io.IOException;
+
+public class TestInputStream extends TestCase {
+    public void testRead() throws IOException {
+        InputStream is = new MockInputStream(new byte[] { (byte) 0x80, 0x01,
+                                                          (byte) 0xFF, 0x7F,
+                                                          (byte) 0x80, (byte) 0x80, 0x01,
+                                                          (byte) 0x81, (byte) 0x80, 0x01,
+                                                          0x06, 'L', 'u', 'c', 'e', 'n', 'e'});
+        assertEquals(128,is.readVInt());
+        assertEquals(16383,is.readVInt());
+        assertEquals(16384,is.readVInt());
+        assertEquals(16385,is.readVInt());
+        assertEquals("Lucene",is.readString());
+    }
+}