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+package PWC257;
+
+/**
+ * PL/Java implementation for PWC 257
+ * Task 1
+ * See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-257>
+ *
+ *
+ * To compile on the local machine:
+
+ $ export JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64/ # if not already set
+ $ mvn clean build
+ $ scp target/PWC257.jar luca@venkman:/tmp
+
+
+ * To install into PostgreSQL execute:
+
+ select sqlj.install_jar( 'file:///tmp/PWC257.jar', 'PWC257', true );
+
+ select 257.task1_pljava();
+
+ and then to redeploy:
+
+ select sqlj.replace_jar( 'file:///tmp/PWC257.jar', 'PWC257', true );
+
+*/
+
+import org.postgresql.pljava.*;
+import org.postgresql.pljava.annotation.Function;
+import static org.postgresql.pljava.annotation.Function.Effects.IMMUTABLE;
+import static org.postgresql.pljava.annotation.Function.OnNullInput.RETURNS_NULL;
+
+import org.postgresql.pljava.ResultSetProvider;
+import java.sql.ResultSet;
+
+import java.util.*;
+import java.sql.SQLException;
+import java.util.logging.*;
+
+public class Task1 implements ResultSetProvider {
+
+ private final static Logger logger = Logger.getAnonymousLogger();
+
+ @Function( schema = "pwc257",
+ onNullInput = RETURNS_NULL,
+ effects = IMMUTABLE )
+ public static final ResultSetProvider task1_pljava( int[] numbers ) throws SQLException {
+ logger.log( Level.INFO, "Entering task1_pljava" );
+ return new Task1( numbers );
+
+ }
+
+ public Task1( int[] nums ) {
+ numbers = nums;
+ }
+
+ private int[] numbers;
+
+ @Override
+ public boolean assignRowValues(ResultSet receiver, int currentRow)
+ throws SQLException {
+
+ if ( currentRow >= numbers.length )
+ return false;
+
+ int current = numbers[ currentRow ];
+
+ int count = 0;
+ for ( int other : numbers )
+ if ( other < current )
+ count++;
+
+ receiver.updateInt( 1, count );
+ return true;
+
+ }
+
+
+
+ @Override
+ public void close() { }
+
+}