diff --git a/pom.xml b/pom.xml
index 9ce484af77b07d390741e2a61b088ea497643a74..ce4dc4876f751cdd8faf12155897ce829e59af36 100644
--- a/pom.xml
+++ b/pom.xml
@@ -3,6 +3,10 @@
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
+ <properties>
+ <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+ </properties>
+
<groupId>edu.unl.cse.csv_io</groupId>
<artifactId>csv_io</artifactId>
@@ -41,6 +45,11 @@
<version>4.12</version>
<scope>test</scope>
</dependency>
+ <dependency>
+ <groupId>com.opencsv</groupId>
+ <artifactId>opencsv</artifactId>
+ <version>5.0</version>
+ </dependency>
</dependencies>
</project>
diff --git a/src/main/java/edu/unl/cse/csv_io/CSVReaderWriter.java b/src/main/java/edu/unl/cse/csv_io/CSVReaderWriter.java
index 90d7e477b3c9eb2631acf018f586cf77be5ecbfe..29d1ec0a47175298a9eb7ee8ee805b843e2b27fb 100644
--- a/src/main/java/edu/unl/cse/csv_io/CSVReaderWriter.java
+++ b/src/main/java/edu/unl/cse/csv_io/CSVReaderWriter.java
@@ -2,28 +2,68 @@
* CSV Reader/Writer, copyright (c) 2019 Christopher A. Bohn, bohn@unl.edu.
*/
-
package edu.unl.cse.csv_io;
+import com.opencsv.CSVReaderHeaderAware;
+import com.opencsv.CSVReaderHeaderAwareBuilder;
+import com.opencsv.exceptions.CsvValidationException;
+
import java.io.*;
import java.net.URL;
import java.util.*;
public class CSVReaderWriter {
- // this does not (yet) handle data elements that include commas and/or are surrounded by quotation marks
- private static final String DELIMTER = ",";
- private static final char BYTE_ORDER_MARK = '\ufeff';
+ @SuppressWarnings("WeakerAccess")
+ public static Set<Map<String, String>> readCSVasSet(String filename) {
+ Set<Map<String, String>> csvSet = null;
+ try (InputStreamReader inputStreamReader = new InputStreamReader(Objects.requireNonNull(
+ CSVReaderWriter.class.getClassLoader().getResourceAsStream("csv/" + filename)))) {
+ csvSet = (Set<Map<String, String>>) parseCSV(inputStreamReader, new HashSet<>());
+ } catch (NullPointerException nullPointerException) {
+ System.err.println("Check spelling of file " + filename + ".");
+ System.exit(1);
+ } catch (IOException ioException) {
+ System.err.println("Error loading " + filename + ". " + ioException);
+ System.exit(1);
+ } catch (CsvValidationException csvValidationException) {
+ System.err.println("Could not validate a line in " + filename + ". " + csvValidationException);
+ System.exit(1);
+ }
+ return csvSet;
+ }
+ private static Collection<Map<String, String>> parseCSV(InputStreamReader inputStreamReader,
+ Collection<Map<String, String>> destination)
+ throws IOException, CsvValidationException {
+ Map<String, String> line;
+ try {
+ CSVReaderHeaderAware csvReader = new CSVReaderHeaderAwareBuilder(inputStreamReader).build();
+ while ((line = csvReader.readMap()) != null) {
+ destination.add(line);
+ }
+ } catch (NullPointerException ignored) {
+ // CSVReaderHeaderAwareBuilder.build() throws NullPointerException if inputStreamReader is empty
+ }
+ return destination;
+ }
+
+ /* LEGACY METHODS */
+ @SuppressWarnings("WeakerAccess")
+ public static Set<Map<String, String>> readCSV(String filename) {
+ return readCSVasSet(filename);
+ }
+/*
public static Set<Map<String, String>> readCSV(String filename) {
Set<Map<String, String>> csvSet = null;
ClassLoader classLoader = CSVReaderWriter.class.getClassLoader();
- try(InputStream inputStream = classLoader.getResourceAsStream("csv/"+filename)) {
+ try (InputStream inputStream = classLoader.getResourceAsStream("csv/" + filename)) {
csvSet = parseCSV(inputStream);
} catch (IOException ioException) {
System.err.println("Error loading " + filename + ". " + ioException);
}
return csvSet;
}
+*/
public static boolean writeCSV(String filename, Set<Map<String, String>> data) {
boolean wroteFile = true;
@@ -31,7 +71,7 @@ public class CSVReaderWriter {
URL resource = classLoader.getResource("csv/" + filename);
if (resource != null) {
File file = new File(resource.getPath());
- try(OutputStream outputStream = new FileOutputStream(file)) {
+ try (OutputStream outputStream = new FileOutputStream(file)) {
placeCSVonStream(data, outputStream);
} catch (FileNotFoundException fileNotFoundException) {
System.err.println("Could not open " + filename + "; probably due to a bad pathname. " + fileNotFoundException);
@@ -47,6 +87,16 @@ public class CSVReaderWriter {
return wroteFile;
}
+
+ static Set<Map<String, String>> parseCSV(InputStream inputStream) throws IOException {
+ try {
+ return (Set<Map<String, String>>) parseCSV(new InputStreamReader(inputStream), new HashSet<>());
+ } catch (CsvValidationException csvValidationException) {
+ csvValidationException.printStackTrace();
+ return null;
+ }
+ }
+/*
static Set<Map<String, String>> parseCSV(InputStream inputStream) throws IOException {
Set<Map<String, String>> csvSet = new HashSet<>();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
@@ -57,14 +107,15 @@ public class CSVReaderWriter {
String[] elements = line.split(DELIMTER);
if (header) {
if (elements[0].charAt(0) == BYTE_ORDER_MARK) {
- elements[0] = elements[0].substring(1); // remove text-encoding character sometimes added by Excel
+ elements[0] = elements[0].substring(1); // remove text-encoding character sometimes added by
+ // Excel
}
fieldNames.addAll(Arrays.asList(elements));
header = false;
} else {
Map<String, String> row = new HashMap<>();
int column = 0;
- for (String element: elements) {
+ for (String element : elements) {
row.put(fieldNames.get(column++), element);
}
csvSet.add(row);
@@ -72,35 +123,66 @@ public class CSVReaderWriter {
}
return csvSet;
}
+*/
static void placeCSVonStream(Set<Map<String, String>> data, OutputStream outputStream) {
PrintStream writer = new PrintStream(outputStream);
Set<String> fieldNames = null;
int number_of_fields = 0;
- for (Map<String, String> row: data) {
+ for (Map<String, String> row : data) {
int field_number = 0;
if (fieldNames == null) {
fieldNames = row.keySet();
number_of_fields = fieldNames.size();
- for (String field: fieldNames) {
+ for (String field : fieldNames) {
writer.print(field);
- writer.print(++field_number<number_of_fields ? "," : "\n");
+ writer.print(++field_number < number_of_fields ? "," : "\n");
}
}
field_number = 0;
- for (String field: fieldNames) {
+ for (String field : fieldNames) {
String value = row.get(field);
writer.print(value != null ? value : "");
- writer.print(++field_number<number_of_fields ? "," : "\n");
+ writer.print(++field_number < number_of_fields ? "," : "\n");
}
}
}
+ /*
+ public static void main(String[] args) {
+ Set<Map<String, String>> demo = readCSV("demo.csv");
+ boolean success = writeCSV("out.csv", demo);
+ System.out.println(success ? "Wrote file!" : "Didn't write file");
+ }
+ */
/*
public static void main(String[] args) {
- Set<Map<String, String>> demo = readCSV("demo.csv");
- boolean success = writeCSV("out.csv", demo);
- System.out.println(success ? "Wrote file!" : "Didn't write file");
+ Set<Map<String,String>> students = readCSV("students.csv");
+ for (Map<String,String> student: students) {
+ System.out.println(student.get("Name"));
+ }
+ }
+*//*
+ public static void main(String[] args) {
+ Set<Map<String, String>> courses = readCSV("courses.csv");
+ for (Map<String, String> course : courses) {
+ String foo = course.get("URL");
+ if (foo == null) {
+ foo = "Null object";
+ } else if (foo.equals("")) foo = "Empty String";
+ System.out.println(course.get("CourseID") + " " + course.get("Section") + " " + foo + " " + course.get(
+ "Prerequisite1"));
+ }
+ }*/
+ public static void main(String[] args) {
+ Set<Map<String, String>> courses = readCSV("empty.csv");
+ for (Map<String, String> course : courses) {
+ String foo = course.get("URL");
+ if (foo == null) {
+ foo = "Null object";
+ } else if (foo.equals("")) foo = "Empty String";
+ System.out.println(course.get("CourseID") + " " + course.get("Section") + " " + foo + " " + course.get(
+ "Prerequisite1"));
+ }
}
-*/
}
diff --git a/src/main/resources/csv/empty.csv b/src/main/resources/csv/empty.csv
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
diff --git a/src/test/java/edu/unl/cse/csv_io/CSVReaderWriterTest.java b/src/test/java/edu/unl/cse/csv_io/CSVReaderWriterTest.java
index 5b8641b2475ff8ae3dbef6303d849dc75158bb17..12e27b653371350ea56e1a19523203106f8f567e 100644
--- a/src/test/java/edu/unl/cse/csv_io/CSVReaderWriterTest.java
+++ b/src/test/java/edu/unl/cse/csv_io/CSVReaderWriterTest.java
@@ -10,6 +10,7 @@ import java.util.*;
import static org.junit.Assert.*;
import static org.hamcrest.CoreMatchers.*;
+@SuppressWarnings("unchecked") // pee-yew!
public class CSVReaderWriterTest {
private static InputStream inputStream;
private static OutputStream outputStream;
@@ -58,11 +59,12 @@ public class CSVReaderWriterTest {
Set<String> expectedKeys = new HashSet<>(Arrays.asList(headers));
// Oracle -- Rows
Map<String, String> expectedRow = new HashMap<>();
- for (int i=0; i<headers.length; i++) {
+ for (int i = 0; i < headers.length; i++) {
expectedRow.put(headers[i], row[i]);
}
// Compare
- Map<String,String> aRow = (Map<String,String>)result.toArray()[0];
+ assertNotNull(result);
+ Map<String, String> aRow = (Map<String, String>) result.toArray()[0];
assertEquals(expectedKeys, aRow.keySet());
assertTrue(result.contains(expectedRow));
}
@@ -86,21 +88,22 @@ public class CSVReaderWriterTest {
// Oracle -- Rows
Map<String, String>[] expectedRows = new Map[2];
for (int i = 0; i < expectedRows.length; i++) {
- expectedRows[i] = new HashMap<String, String>();
+ expectedRows[i] = new HashMap<>();
for (int j = 0; j < headers.length; j++) {
expectedRows[i].put(headers[j], rows[i][j]);
}
}
// Compare
+ assertNotNull(result);
Map<String, String> aRow = (Map<String, String>) result.toArray()[0];
assertEquals(expectedKeys, aRow.keySet());
- for (Map<String, String> expectedRow: expectedRows) {
+ for (Map<String, String> expectedRow : expectedRows) {
assertTrue(result.contains(expectedRow));
}
}
@Test
- public void testParsingCSVwithOnlyHeaderRow() {
+ public void testParsingCSVWithOnlyHeaderRow() {
// Input
String[] headers = {"header1", "header2"};
String[][] data = {headers};
@@ -146,7 +149,7 @@ public class CSVReaderWriterTest {
String[] headers = {"header1", "header2"};
String[][] rows = {{"datum1", "datum2"}, {"datum3", "datum4"}};
Map<String, String>[] inputRows = new Map[2];
- for (int i=0; i<inputRows.length; i++) {
+ for (int i = 0; i < inputRows.length; i++) {
inputRows[i] = new HashMap<>(2);
inputRows[i].put(headers[0], rows[i][0]);
inputRows[i].put(headers[1], rows[i][1]);