org.apache.commons.csv.CSVPrinter.printRecords(ResultSet) now writes one

record at a time using a lock

Author: garydgregory

pom.xml

@@ -68,6 +68,12 @@
       <version>${commons.jmh.version}</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.github.spotbugs</groupId>
+      <artifactId>spotbugs-annotations</artifactId>
+      <version>${commons.spotbugs.impl.version}</version>
+      <optional>true</optional>
+    </dependency>
   </dependencies>
   <scm>
     <connection>scm:git:http://gitbox.apache.org/repos/asf/commons-csv.git</connection>

src/changes/changes.xml

@@ -44,6 +44,7 @@
       <!-- FIX -->
       <action type="fix" issue="CSV-318" dev="ggregory" due-to="Joseph Shraibman, Gary Gregory">CSVPrinter.printRecord(Stream) hangs if given a parallel stream.</action>
       <action type="fix" issue="CSV-318" dev="ggregory" due-to="Joseph Shraibman, Gary Gregory">CSVPrinter now uses an internal lock instead of synchronized methods.</action>
+      <action type="fix" dev="ggregory" due-to="Gary Gregory">org.apache.commons.csv.CSVPrinter.printRecords(ResultSet) now writes one record at a time using a lock.</action>
       <!-- ADD -->
       <!-- UPDATE -->
       <action type="update" dev="ggregory" due-to="Gary Gregory">Bump commons-io:commons-io from 2.18.0 to 2.19.0.</action>

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

@@ -40,6 +40,8 @@
 
 import org.apache.commons.io.function.IOStream;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
 /**
  * Prints values in a {@link CSVFormat CSV format}.
  *
@@ -151,14 +153,10 @@ public void close(final boolean flush) throws IOException {
      * @throws IOException
      *             If an I/O error occurs
      */
+    @SuppressFBWarnings(value = "AT_NONATOMIC_OPERATIONS_ON_SHARED_VARIABLE", justification = "https://github.com/spotbugs/spotbugs/issues/3428")
     private void endOfRecord() throws IOException {
-        lock.lock();
-        try {
-            println();
-            recordCount++;
-        } finally {
-            lock.unlock();
-        }
+        println();
+        recordCount++;
     }
 
     /**
@@ -494,21 +492,26 @@ public void printRecords(final Object... values) throws IOException {
     public void printRecords(final ResultSet resultSet) throws SQLException, IOException {
         final int columnCount = resultSet.getMetaData().getColumnCount();
         while (resultSet.next() && format.useRow(resultSet.getRow())) {
-            for (int i = 1; i <= columnCount; i++) {
-                final Object object = resultSet.getObject(i);
-                if (object instanceof Clob) {
-                    try (Reader reader = ((Clob) object).getCharacterStream()) {
-                        print(reader);
+            lock.lock();
+            try {
+                for (int i = 1; i <= columnCount; i++) {
+                    final Object object = resultSet.getObject(i);
+                    if (object instanceof Clob) {
+                        try (Reader reader = ((Clob) object).getCharacterStream()) {
+                            print(reader);
+                        }
+                    } else if (object instanceof Blob) {
+                        try (InputStream inputStream = ((Blob) object).getBinaryStream()) {
+                            print(inputStream);
+                        }
+                    } else {
+                        print(object);
                     }
-                } else if (object instanceof Blob) {
-                    try (InputStream inputStream = ((Blob) object).getBinaryStream()) {
-                        print(inputStream);
-                    }
-                } else {
-                    print(object);
                 }
+                endOfRecord();
+            } finally {
+                lock.unlock();
             }
-            endOfRecord();
         }
     }