[CSV-168] CsvFormat.nullString should not be escaped. [CSV-170]

CSVFormat.MYSQL nullString should be "\N".

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/csv/trunk@1725407 13f79535-47bb-0310-9956-ffa450edef68

src/changes/changes.xml

@@ -42,6 +42,8 @@
       <action issue="CSV-153" type="update" dev="britter" due-to="Wren">CSVPrinter doesn't skip creation of header record if skipHeaderRecord is set to true</action>
       <action issue="CSV-159" type="add" dev="ggregory" due-to="Yamil Medina">Add IgnoreCase option for accessing header names</action>
       <action issue="CSV-169" type="add" dev="ggregory" due-to="Gary Gregory">The null string should be case-sensitive when reading records</action>
+      <action issue="CSV-168" type="fix" dev="ggregory" due-to="Gary Gregory, cornel creanga">CsvFormat.nullString should not be escaped</action>
+      <action issue="CSV-170" type="fix" dev="ggregory" due-to="Gary Gregory, cornel creanga">CSVFormat.MYSQL nullString should be "\N"</action>
     </release>
     <release version="1.2" date="2015-08-24" description="Feature and bug fix release">
       <action issue="CSV-145" type="fix" dev="ggregory" due-to="Frank Ulbricht">CSVFormat.with* methods clear the header comments</action>

src/main/java/org/apache/commons/csv/CSVFormat.java

@@ -296,7 +296,7 @@ public final class CSVFormat implements Serializable {
      *
      * <p>
      * This is a tab-delimited format with a LF character as the line separator. Values are not quoted and special
-     * characters are escaped with '\'.
+     * characters are escaped with {@code '\'}. The default NULL string is {@code "\\N"}.
      * </p>
      *
      * <p>
@@ -308,6 +308,7 @@ public final class CSVFormat implements Serializable {
      * <li>withRecordSeparator('\n')</li>
      * <li>withIgnoreEmptyLines(false)</li>
      * <li>withEscape('\\')</li>
+     * <li>withNullString("\\N")</li>
      * </ul>
      *
      * @see Predefined#MySQL
@@ -315,7 +316,7 @@ public final class CSVFormat implements Serializable {
      *      http://dev.mysql.com/doc/refman/5.1/en/load-data.html</a>
      */
     public static final CSVFormat MYSQL = DEFAULT.withDelimiter(TAB).withEscape(BACKSLASH).withIgnoreEmptyLines(false)
-            .withQuote(null).withRecordSeparator(LF);
+            .withQuote(null).withRecordSeparator(LF).withNullString("\\N");
 
     /**
      * Returns true if the given character is a line break character.

src/main/java/org/apache/commons/csv/CSVPrinter.java

@@ -136,7 +136,9 @@ public final class CSVPrinter implements Flushable, Closeable {
         if (!newRecord) {
             out.append(format.getDelimiter());
         }
-        if (format.isQuoteCharacterSet()) {
+        if (object == null) {
+            out.append(value);
+        } else if (format.isQuoteCharacterSet()) {
             // the original object is needed so can check for Number
             printAndQuote(object, value, offset, len);
         } else if (format.isEscapeCharacterSet()) {

src/test/java/org/apache/commons/csv/CSVPrinterTest.java

@@ -18,6 +18,7 @@
 package org.apache.commons.csv;
 
 import static org.apache.commons.csv.Constants.CR;
+import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 
@@ -35,6 +36,7 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Random;
 
+import org.apache.commons.lang3.ObjectUtils;
 import org.junit.Test;
 
 /**
@@ -44,6 +46,8 @@ import org.junit.Test;
  */
 public class CSVPrinterTest {
 
+    private static final int ITERATIONS_FOR_RANDOM_TEST = 50000;
+    
     private final String recordSeparator = CSVFormat.DEFAULT.getRecordSeparator();
 
     private static String printable(final String s) {
@@ -65,14 +69,7 @@ public class CSVPrinterTest {
         final int nLines = r.nextInt(4) + 1;
         final int nCol = r.nextInt(3) + 1;
         // nLines=1;nCol=2;
-        final String[][] lines = new String[nLines][];
+        final String[][] lines = generateLines(nLines, nCol);
-        for (int i = 0; i < nLines; i++) {
-            final String[] line = new String[nCol];
-            lines[i] = line;
-            for (int j = 0; j < nCol; j++) {
-                line[j] = randStr();
-            }
-        }
 
         final StringWriter sw = new StringWriter();
         final CSVPrinter printer = new CSVPrinter(sw, format);
@@ -90,10 +87,26 @@ public class CSVPrinterTest {
         final CSVParser parser = CSVParser.parse(result, format);
         final List<CSVRecord> parseResult = parser.getRecords();
 
-        Utils.compare("Printer output :" + printable(result), lines, parseResult);
+        String[][] expected = lines.clone();
+        for (int i = 0; i < expected.length; i++) {
+            expected[i] = expectNulls(expected[i], format);
+        }
+        Utils.compare("Printer output :" + printable(result), expected, parseResult);
         parser.close();
     }
 
+    private String[][] generateLines(final int nLines, final int nCol) {
+        final String[][] lines = new String[nLines][];
+        for (int i = 0; i < nLines; i++) {
+            final String[] line = new String[nCol];
+            lines[i] = line;
+            for (int j = 0; j < nCol; j++) {
+                line[j] = randStr();
+            }
+        }
+        return lines;
+    }
+
     private void doRandom(final CSVFormat format, final int iter) throws Exception {
         for (int i = 0; i < iter; i++) {
             doOneRandom(format);
@@ -189,8 +202,8 @@ public class CSVPrinterTest {
     public void testExcelPrintAllIterableOfLists() throws IOException {
         final StringWriter sw = new StringWriter();
         final CSVPrinter printer = new CSVPrinter(sw, CSVFormat.EXCEL);
-        printer.printRecords(Arrays.asList(new List[] { Arrays.asList("r1c1", "r1c2"),
+        printer.printRecords(
-                Arrays.asList("r2c1", "r2c2") }));
+                Arrays.asList(new List[] { Arrays.asList("r1c1", "r1c2"), Arrays.asList("r2c1", "r2c2") }));
         assertEquals("r1c1,r1c2" + recordSeparator + "r2c1,r2c2" + recordSeparator, sw.toString());
         printer.close();
     }
@@ -301,6 +314,131 @@ public class CSVPrinterTest {
         printer.close();
     }
 
+    @Test
+    public void testMySqlNullStringDefault() throws IOException {
+        assertEquals("\\N", CSVFormat.MYSQL.getNullString());
+    }
+
+    @Test
+    public void testMySqlNullOutput() throws IOException {
+        Object[] s = new String[] { "NULL", null };
+        CSVFormat format = CSVFormat.MYSQL.withQuote('"').withNullString("NULL").withQuoteMode(QuoteMode.NON_NUMERIC);
+        StringWriter writer = new StringWriter();
+        CSVPrinter printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        String expected = "\"NULL\"\tNULL\n";
+        assertEquals(expected, writer.toString());
+        String[] record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(new Object[2], record0);
+
+        s = new String[] { "\\N", null };
+        format = CSVFormat.MYSQL.withNullString("\\N");
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "\\\\N\t\\N\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+
+        s = new String[] { "\\N", "A" };
+        format = CSVFormat.MYSQL.withNullString("\\N");
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "\\\\N\tA\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+
+        s = new String[] { "\n", "A" };
+        format = CSVFormat.MYSQL.withNullString("\\N");
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "\\n\tA\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+
+        s = new String[] { "", null };
+        format = CSVFormat.MYSQL.withNullString("NULL");
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "\tNULL\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+
+        s = new String[] { "", null };
+        format = CSVFormat.MYSQL;
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "\t\\N\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+
+        s = new String[] { "\\N", "", "\u000e,\\\r" };
+        format = CSVFormat.MYSQL;
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "\\\\N\t\t\u000e,\\\\\\r\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+
+        s = new String[] { "NULL", "\\\r" };
+        format = CSVFormat.MYSQL;
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "NULL\t\\\\\\r\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+
+        s = new String[] { "\\\r" };
+        format = CSVFormat.MYSQL;
+        writer = new StringWriter();
+        printer = new CSVPrinter(writer, format);
+        printer.printRecord(s);
+        printer.close();
+        expected = "\\\\\\r\n";
+        assertEquals(expected, writer.toString());
+        record0 = toFirstRecordValues(expected, format);
+        assertArrayEquals(expectNulls(s, format), record0);
+    }
+
+    /**
+     * Converts an input CSV array into expected output values WRT NULLs. NULL strings are converted to null values
+     * because the parser will convert these strings to null.
+     */
+    private <T> T[] expectNulls(T[] original, CSVFormat csvFormat) {
+        T[] fixed = original.clone();
+        for (int i = 0; i < fixed.length; i++) {
+            if (ObjectUtils.equals(csvFormat.getNullString(), fixed[i])) {
+                fixed[i] = null;
+            }
+        }
+        return fixed;
+    }
+
+    private String[] toFirstRecordValues(final String expected, CSVFormat format) throws IOException {
+        return CSVParser.parse(expected, format).getRecords().get(0).values();
+    }
+
     @Test
     public void testPrinter1() throws IOException {
         final StringWriter sw = new StringWriter();
@@ -429,11 +567,28 @@ public class CSVPrinterTest {
     }
 
     @Test
-    public void testRandom() throws Exception {
+    public void testRandomDefault() throws Exception {
-        final int iter = 10000;
+        doRandom(CSVFormat.DEFAULT, ITERATIONS_FOR_RANDOM_TEST);
-        doRandom(CSVFormat.DEFAULT, iter);
+    }
-        doRandom(CSVFormat.EXCEL, iter);
+
-        doRandom(CSVFormat.MYSQL, iter);
+    @Test
+    public void testRandomExcel() throws Exception {
+        doRandom(CSVFormat.EXCEL, ITERATIONS_FOR_RANDOM_TEST);
+    }
+
+    @Test
+    public void testRandomMySql() throws Exception {
+        doRandom(CSVFormat.MYSQL, ITERATIONS_FOR_RANDOM_TEST);
+    }
+
+    @Test
+    public void testRandomTdf() throws Exception {
+        doRandom(CSVFormat.TDF, ITERATIONS_FOR_RANDOM_TEST);
+    }
+
+    @Test
+    public void testRandomRfc4180() throws Exception {
+        doRandom(CSVFormat.RFC4180, ITERATIONS_FOR_RANDOM_TEST);
     }
 
     @Test
@@ -496,6 +651,42 @@ public class CSVPrinterTest {
         printer.close();
     }
 
+    @Test
+    public void testEscapeBackslash() throws IOException {
+        StringWriter sw = new StringWriter();
+        final char quoteChar = '\'';
+        final String eol = "\r\n";
+        CSVPrinter printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(quoteChar));
+        printer.print("\\");
+        printer.close();
+        assertEquals("'\\'", sw.toString());
+
+        sw = new StringWriter();
+        printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(quoteChar));
+        printer.print("\\\r");
+        printer.close();
+        assertEquals("'\\\r'", sw.toString());
+
+        sw = new StringWriter();
+        printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(quoteChar));
+        printer.print("X\\\r");
+        printer.close();
+        assertEquals("'X\\\r'", sw.toString());
+
+        sw = new StringWriter();
+        printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(quoteChar));
+        printer.printRecord(new Object[] { "\\\r" });
+        printer.close();
+        assertEquals("'\\\r'" + eol, sw.toString());
+
+        sw = new StringWriter();
+        printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(quoteChar));
+        printer.print("\\\\");
+        printer.close();
+        assertEquals("'\\\\'", sw.toString());
+
+    }
+
     @Test
     public void testPlainEscaped() throws IOException {
         final StringWriter sw = new StringWriter();
@@ -549,8 +740,7 @@ public class CSVPrinterTest {
     @Test
     public void testHeader() throws IOException {
         final StringWriter sw = new StringWriter();
-        final CSVPrinter printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(null)
+        final CSVPrinter printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(null).withHeader("C1", "C2", "C3"));
-                .withHeader("C1", "C2", "C3"));
         printer.printRecord("a", "b", "c");
         printer.printRecord("x", "y", "z");
         assertEquals("C1,C2,C3\r\na,b,c\r\nx,y,z\r\n", sw.toString());
@@ -571,8 +761,8 @@ public class CSVPrinterTest {
     public void testSkipHeaderRecordTrue() throws IOException {
         // functionally identical to testHeaderNotSet, used to test CSV-153
         final StringWriter sw = new StringWriter();
-        final CSVPrinter printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(null)
+        final CSVPrinter printer = new CSVPrinter(sw,
-                .withHeader("C1", "C2", "C3").withSkipHeaderRecord(true));
+                CSVFormat.DEFAULT.withQuote(null).withHeader("C1", "C2", "C3").withSkipHeaderRecord(true));
         printer.printRecord("a", "b", "c");
         printer.printRecord("x", "y", "z");
         assertEquals("a,b,c\r\nx,y,z\r\n", sw.toString());
@@ -583,8 +773,8 @@ public class CSVPrinterTest {
     public void testSkipHeaderRecordFalse() throws IOException {
         // functionally identical to testHeader, used to test CSV-153
         final StringWriter sw = new StringWriter();
-        final CSVPrinter printer = new CSVPrinter(sw, CSVFormat.DEFAULT.withQuote(null)
+        final CSVPrinter printer = new CSVPrinter(sw,
-                .withHeader("C1", "C2", "C3").withSkipHeaderRecord(false));
+                CSVFormat.DEFAULT.withQuote(null).withHeader("C1", "C2", "C3").withSkipHeaderRecord(false));
         printer.printRecord("a", "b", "c");
         printer.printRecord("x", "y", "z");
         assertEquals("C1,C2,C3\r\na,b,c\r\nx,y,z\r\n", sw.toString());
@@ -597,7 +787,8 @@ public class CSVPrinterTest {
         final Date now = new Date();
         final CSVFormat format = CSVFormat.EXCEL;
         final CSVPrinter csvPrinter = printWithHeaderComments(sw, now, format);
-        assertEquals("# Generated by Apache Commons CSV 1.1\r\n# " + now + "\r\nCol1,Col2\r\nA,B\r\nC,D\r\n", sw.toString());
+        assertEquals("# Generated by Apache Commons CSV 1.1\r\n# " + now + "\r\nCol1,Col2\r\nA,B\r\nC,D\r\n",
+                sw.toString());
         csvPrinter.close();
     }
 
@@ -607,7 +798,8 @@ public class CSVPrinterTest {
         final Date now = new Date();
         final CSVFormat format = CSVFormat.TDF;
         final CSVPrinter csvPrinter = printWithHeaderComments(sw, now, format);
-        assertEquals("# Generated by Apache Commons CSV 1.1\r\n# " + now + "\r\nCol1\tCol2\r\nA\tB\r\nC\tD\r\n", sw.toString());
+        assertEquals("# Generated by Apache Commons CSV 1.1\r\n# " + now + "\r\nCol1\tCol2\r\nA\tB\r\nC\tD\r\n",
+                sw.toString());
         csvPrinter.close();
     }