Possibility to read MEMO field as binary data, regardless of field de…

…fintion

Fixes #98

src/main/java/com/linuxense/javadbf/DBFMemoFile.java

@@ -144,7 +144,7 @@ protected byte[] readBinary(int block) {
 
 	protected Object readData(int block, DBFDataType type) {
 		long blockStart = this.blockSize * (long) block;
-		DBFDataType usedType = type;
+		DBFDataType usedType = null;
 		try {
 			seek(blockStart);
 			byte[] blockData = new byte[this.blockSize];
@@ -196,10 +196,14 @@ else if (intType == 0) {
 				}
 			}
 			byte[] data = baos.toByteArray();
-			if (usedType != DBFDataType.MEMO) {
-				return data;
+
+			if (usedType == null) {
+				usedType = type;
 			}
-			return new String(data, charset);
+			if (usedType == DBFDataType.MEMO && type == DBFDataType.MEMO){
+				return new String(data, charset);
+			}
+			return data;
 
 		}
 		catch (IOException ex) {

src/main/java/com/linuxense/javadbf/DBFReader.java

@@ -37,8 +37,10 @@
 import java.util.Date;
 import java.util.GregorianCalendar;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.TimeZone;
 
 /**
@@ -155,6 +157,8 @@ public class DBFReader extends DBFBase implements Closeable {
 	private Map<String, Integer> mapFieldNames = new HashMap<String, Integer>();
 
 	private boolean showDeletedRows = false;
+
+	private Set<String> fieldsAsBinary = new HashSet<>();
 
 	/**
 	 * Intializes a DBFReader object.
@@ -268,7 +272,26 @@ private Map<String, Integer> createMapFieldNames(DBFField[] fieldArray) {
 		}		
 		return Collections.unmodifiableMap(fieldNames);
 	}
+
+	/**
+	 * Set the list of memo fields to be readed as binary.
+	 * By default memo fields are retrieved as Strings, but if you know they store binary data
+	 * you can set the names of the memo fields to be recovered unproceesded as byte[]
+	 * @param names name of the memol fields to be treated as binary data.
+	 */
 
+	public void setReadMemoFieldsAsBinary(String... names) {
+		Set<String> newSet = new HashSet<>();
+		for (String name: names) {
+			if (name != null) {
+				String name1 = name.toUpperCase().trim();
+				if (name1.length() > 0) {
+					newSet.add(name1);
+				}
+			}
+		}
+		this.fieldsAsBinary = newSet;
+	}
 
 	/**
 		Returns the number of records in the DBF. This number includes deleted (hidden) records
@@ -534,7 +557,11 @@ private Object readMemoField(DBFField field) throws IOException {
 			nBlock = DBFUtils.readLittleEndianInt(this.dataInputStream);
 		}
 		if (this.memoFile != null && nBlock != null) {
-			return memoFile.readData(nBlock.intValue(), field.getType());
+			DBFDataType type = field.getType();
+			if (type == DBFDataType.MEMO && fieldsAsBinary.contains(field.getName().toUpperCase())) {
+				type = DBFDataType.BINARY;
+			}
+			return memoFile.readData(nBlock.intValue(), type);
 		}
 		return null;
 	}

src/test/java/com/linuxense/javadbf/bug98/ReadMemoAsBinaryTest.java

@@ -0,0 +1,40 @@
+package com.linuxense.javadbf.bug98;
+
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import com.linuxense.javadbf.DBFReader;
+import com.linuxense.javadbf.DBFRow;
+import com.linuxense.javadbf.DBFUtils;
+
+public class ReadMemoAsBinaryTest {
+
+	public ReadMemoAsBinaryTest() {
+		super();
+	}
+
+	@Test
+	public void testReadMemoAsBinary() throws Exception {
+		File file = new File("src/test/resources/fixtures/dbase_8b.dbf");
+		DBFReader reader  = null;
+		try {
+			reader = new DBFReader( new BufferedInputStream(new FileInputStream(file)));
+			reader.setMemoFile(new File("src/test/resources/fixtures/dbase_8b.dbt"));
+			reader.setReadMemoFieldsAsBinary("MEMO");
+			DBFRow row = null;
+			while ((row = reader.nextRow()) != null) {
+				byte[] data = row.getBytes("MEMO");
+				Assertions.assertTrue(data == null || data instanceof byte[]);
+			}
+
+		}
+		finally {
+			DBFUtils.close(reader);
+		}
+	}
+
+}