added extra constructor into JBBPParser and added test for custom type parsing "BCD"

Author: raydac

src/main/java/com/igormaznitsa/jbbp/JBBPParser.java

@@ -579,6 +579,20 @@ public static JBBPParser prepare(final String script) {
     return JBBPParser.prepare(script, JBBPBitOrder.LSB0);
   }
 
+  /**
+   * Prepare a parser for a script with default bit order (LSB0) use and with defined custom type field processor.
+   *
+   * @param script a text script contains field order and types reference, it
+   * must not be null
+   * @param customFieldTypeProcessor custom field type processor, can be null
+   * @return the prepared parser for the script
+   * @see JBBPBitOrder#LSB0
+   * @since 1.2.0
+   */
+  public static JBBPParser prepare(final String script, final JBBPCustomFieldTypeProcessor customFieldTypeProcessor) {
+    return JBBPParser.prepare(script, JBBPBitOrder.LSB0, customFieldTypeProcessor, 0);
+  }
+
   /**
    * Prepare a parser for a script with default bit order (LSB0) use and special flags
    * 

src/test/java/com/igormaznitsa/jbbp/it/PackedBCDCustomFieldTest.java

@@ -0,0 +1,106 @@
+/*
+ * Copyright 2015 Igor Maznitsa.
+ *
+ * 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.igormaznitsa.jbbp.it;
+
+import com.igormaznitsa.jbbp.JBBPCustomFieldTypeProcessor;
+import com.igormaznitsa.jbbp.JBBPParser;
+import com.igormaznitsa.jbbp.compiler.JBBPNamedFieldInfo;
+import com.igormaznitsa.jbbp.compiler.tokenizer.JBBPFieldTypeParameterContainer;
+import com.igormaznitsa.jbbp.exceptions.JBBPCompilationException;
+import com.igormaznitsa.jbbp.io.*;
+import com.igormaznitsa.jbbp.model.*;
+import java.io.IOException;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+
+public class PackedBCDCustomFieldTest implements JBBPCustomFieldTypeProcessor {
+
+  private static final String [] types = new String[]{"bcd", "sbcd"};
+  
+  public String[] getCustomFieldTypes() {
+    return types;
+  }
+
+  public boolean isAllowed(final JBBPFieldTypeParameterContainer fieldType, final String fieldName, final int extraData, final boolean isArray) {
+    if (fieldType.getByteOrder() == JBBPByteOrder.LITTLE_ENDIAN){
+      System.err.println("Packed Decimal does not support little endian...using big endian instead");
+      return false;
+    }
+    
+    return extraData>0 && extraData<15;
+  }
+
+  public static long readValueFromPackedDecimal(final JBBPBitInputStream in, final int len, final boolean signed) throws IOException {
+    final byte [] data = in.readByteArray(len);
+    
+    StringBuilder digitStr = new StringBuilder();
+    for (int i = 0; i < len * 2; i++) {
+      byte currentByte = data[i / 2];
+      byte digit = (i % 2 == 0) ? (byte) ((currentByte & 0xff) >>> 4) : (byte) (currentByte & 0x0f);
+      if (digit < 10) {
+        digitStr.append(digit);
+      }
+    }
+
+    if (signed) {
+      byte sign = (byte) (data[len - 1] & 0x0f);
+      if (sign == 0x0b || sign == 0x0d) {
+        digitStr.insert(0, '-');
+      }
+    }
+
+    return Long.parseLong(digitStr.toString());
+  }
+
+  
+  public JBBPAbstractField readCustomFieldType(final JBBPBitInputStream in, final JBBPBitOrder bitOrder, final int parserFlags, final JBBPFieldTypeParameterContainer customTypeFieldInfo, JBBPNamedFieldInfo fieldName, int extraData, boolean readWholeStream, int arrayLength) throws IOException {
+    final boolean signed = "sbcd".equals(customTypeFieldInfo.getTypeName());
+    
+    if (readWholeStream){
+      throw new UnsupportedOperationException("Whole stream reading unsupported");
+    }else{
+      if (arrayLength<=0){
+        return new JBBPFieldLong(fieldName, readValueFromPackedDecimal(in, extraData, signed));
+      }else{
+        final long [] result = new long[arrayLength];
+        for(int i=0;i<arrayLength;i++){
+          result[i] = readValueFromPackedDecimal(in, extraData, signed);
+        }
+        return new JBBPFieldArrayLong(fieldName, result);
+      }
+    }
+  }
+  
+  @Test
+  public void testParse_SingleDefaultNonamedPackedDecimal_Default() throws Exception {
+    final JBBPParser parser = JBBPParser.prepare("bcd:4;",this);
+    final JBBPFieldStruct result = parser.parse(new byte[]{0x12, 0x34, 0x56, 0x7F});
+    assertEquals(1234567L, result.findFieldForType(JBBPFieldLong.class).getAsLong());
+  }
+
+  @Test
+  public void testParse_SingleDefaultNonamedPackedDecimal_BigEndian() throws Exception {
+    final JBBPParser parser = JBBPParser.prepare(">bcd:4;", this);
+    final JBBPFieldStruct result = parser.parse(new byte[]{0x12, 0x34, 0x56, 0x7F});
+    assertEquals(1234567L, result.findFieldForType(JBBPFieldLong.class).getAsLong());
+  }
+
+  @Test(expected = JBBPCompilationException.class)
+  public void testParse_SingleDefaultNonamedPackedDecimal_LittleEndian_Exception() throws Exception {
+    final JBBPParser parser = JBBPParser.prepare("<bcd:4;", this);
+  }  
+  
+}