output CSV with BOM if output format is UTF-8 or UTF-16

output CSV with BOM if output format is UTF-8 or UTF-16

src/main/java/com/salesforce/dataloader/config/AppConfig.java

@@ -334,6 +334,7 @@ public class AppConfig {
     public static final String PROP_EXTRACT_SOQL = "sfdc.extractionSOQL"; //$NON-NLS-1$
     public static final String PROP_SORT_EXTRACT_FIELDS = "sfdc.sortExtractionFields"; //$NON-NLS-1$
     public static final String PROP_EXTRACT_ALL_CAPS_HEADERS="sfdc.extraction.allCapsHeaders";
+    public static final String PROP_EXTRACT_CSV_OUTPUT_BOM="sfdc.extraction.outputByteOrderMark";
     public static final String PROP_LOAD_PRESERVE_WHITESPACE_IN_RICH_TEXT = "sfdc.load.preserveWhitespaceInRichText";
 
     //
@@ -780,6 +781,8 @@ private void setDefaults(Map<String, String> cliOptionsMap) {
         setDefaultValue(PROP_GMT_FOR_DATE_FIELD_VALUE, false);
         setDefaultValue(PROP_SAVE_ALL_PROPS, false);
         setDefaultValue(PROP_EXTRACT_ALL_CAPS_HEADERS, false);
+        setDefaultValue(PROP_EXTRACT_CSV_OUTPUT_BOM, true);
+
     }
 
     /**
@@ -1749,7 +1752,7 @@ public String getCsvEncoding(boolean isWrite) {
         return charset;
     }
 
-    private static String defaultCharsetForCsvReadWrite = null;
+    private static String defaultCharsetForCsvReadWrite = Charset.defaultCharset().name();
     private synchronized static String getDefaultCharsetForCsvReadWrite() {
         if (defaultCharsetForCsvReadWrite != null) {
             return defaultCharsetForCsvReadWrite;

src/main/java/com/salesforce/dataloader/dao/csv/CSVFileWriter.java

@@ -28,9 +28,10 @@
 
 import java.io.BufferedWriter;
 import java.io.FileOutputStream;
-import java.io.FileWriter;
 import java.io.IOException;
 import java.io.OutputStreamWriter;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -70,18 +71,24 @@ public class CSVFileWriter implements DataWriter {
     /**
      * <code>encoding</code> contains a value for output character encoding, blank indicates "use default"
      */
-    private final String encoding;
+    private String encoding;
 
     /**
      * If <code>capitalizedHeadings</code> is true, output header row in caps
      */
     private boolean capitalizedHeadings = false;
     private final char columnDelimiter;
+    private AppConfig appConfig;
 
     public CSVFileWriter(String fileName, AppConfig appConfig, String columnDelimiterStr) {
 
         this.fileName = fileName;
+        this.appConfig = appConfig;
         encoding = appConfig.getCsvEncoding(true);
+        logger.debug("CSV encoding is set to " + Charset.forName(encoding));
+        if (encoding == null) {
+            encoding = Charset.defaultCharset().name();
+        }
         logger.debug(this.getClass().getName(), "encoding used to write to CSV file is " + encoding);
         if (columnDelimiterStr.length() == 0) {
             columnDelimiterStr = AppUtil.COMMA;
@@ -107,19 +114,29 @@ public void checkConnection() throws DataAccessObjectInitializationException {
     @Override
     public void open() throws DataAccessObjectInitializationException {
         try {
-            if (this.encoding != null) {
-                fileOut = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(this.fileName), this.encoding));
-            } else {
-                fileOut = new BufferedWriter(new FileWriter(this.fileName));
-            }
+            FileOutputStream os = new FileOutputStream(this.fileName);
+            OutputStreamWriter osw = new OutputStreamWriter(os, this.encoding);
+            fileOut = new BufferedWriter(osw);
             currentRowNumber = 0;
+            if (appConfig.getBoolean(AppConfig.PROP_EXTRACT_CSV_OUTPUT_BOM)) {
+                os.write(getBOM());
+            }
             setOpen(true);
         } catch (IOException e) {
             String errMsg = Messages.getFormattedString("CSVWriter.errorOpening", this.fileName);
             logger.error(errMsg, e);
             throw new DataAccessObjectInitializationException(errMsg, e);
         }
     }
+
+    private byte[] getBOM() {
+        if (StandardCharsets.UTF_8.equals(Charset.forName(this.encoding))) {
+            return new byte[]{(byte) 0xEF, (byte) 0xBB, (byte) 0xBF};
+        } else if (StandardCharsets.UTF_16.equals(Charset.forName(this.encoding))) {
+            return new byte[]{(byte) 0xFE, (byte) 0xFF};
+        }
+        return new byte[0];
+    }
 
     /*
      * (non-Javadoc)

src/main/resources/labels.properties

@@ -479,6 +479,7 @@ AppConfig.property.description.sfdc.oauth.Sandbox.clientsecret=Specify encrypted
 AppConfig.property.description.sfdc.proxyNtlmDomain=Details documented at https://developer.salesforce.com/docs/atlas.en-us.dataLoader.meta/dataLoader/configuring_the_data_loader.htm
 AppConfig.property.description.sfdc.extractionRequestSize=Details documented at https://developer.salesforce.com/docs/atlas.en-us.dataLoader.meta/dataLoader/loader_params.htm
 AppConfig.property.description.sfdc.extraction.allCapsHeaders=set it to "true" to output extraction field headers in capital letters (uppercase characters).
+AppConfig.property.description.sfdc.extraction.outputByteOrderMark=set to "true" by default. When set to "true", it writes Byte Order Mark (BOM) character if the CSV file is created in UTF-8 format.
 AppConfig.property.description.config.properties.readonly=Do not modify config.properties file even if the user makes changes through Settings dialog.
 AppConfig.property.description.dataAccess.readCharset=Override system default charset by specifying charset to use for import operations. Set it to UTF-8, UTF-16BE, UTF-16LE, UTF-32BE, or UTF-32LE to handle import CSVs with Byte Order Mark (BOM) character.
 AppConfig.property.description.loader.cacheSObjectNamesAndField=Cache object names and fields metadata across multiple operations. Applicable in the UI mode because batch mode executes one operation and stops.