moved java files for pre-convert

java_test/java/com/google/zxing/common/BitSourceBuilder.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.common;
+
+import java.io.ByteArrayOutputStream;
+
+/**
+ * Class that lets one easily build an array of bytes by appending bits at a time.
+ *
+ * @author Sean Owen
+ */
+public final class BitSourceBuilder {
+
+  private final ByteArrayOutputStream output;
+  private int nextByte;
+  private int bitsLeftInNextByte;
+
+  public BitSourceBuilder() {
+    output = new ByteArrayOutputStream();
+    nextByte = 0;
+    bitsLeftInNextByte = 8;
+  }
+
+  public void write(int value, int numBits) {
+    if (numBits <= bitsLeftInNextByte) {
+      nextByte <<= numBits;
+      nextByte |= value;
+      bitsLeftInNextByte -= numBits;
+      if (bitsLeftInNextByte == 0) {
+        output.write(nextByte);
+        nextByte = 0;
+        bitsLeftInNextByte = 8;
+      }
+    } else {
+      int bitsToWriteNow = bitsLeftInNextByte;
+      int numRestOfBits = numBits - bitsToWriteNow;
+      int mask = 0xFF >> (8 - bitsToWriteNow);
+      int valueToWriteNow = (value >>> numRestOfBits) & mask;
+      write(valueToWriteNow, bitsToWriteNow);
+      write(value, numRestOfBits);
+    }
+  }
+
+  public byte[] toByteArray() {
+    if (bitsLeftInNextByte < 8) {
+      write(0, bitsLeftInNextByte);
+    }
+    return output.toByteArray();
+  }
+
+}