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diff --git a/challenge-321/luca-ferrari/pljava/src/main/java/Task1.java b/challenge-321/luca-ferrari/pljava/src/main/java/Task1.java
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+
+
+
+package PWC321;
+
+/**
+ * PL/Java implementation for PWC 321
+ * Task 1
+ * See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-321>
+ *
+ *
+ * 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/PWC321-1.jar  luca@rachel:/tmp
+
+
+ * To install into PostgreSQL execute:
+
+ select sqlj.install_jar( 'file:///tmp/PWC321-1.jar', 'PWC321', true );
+ select sqlj.set_classpath( 'public', 'PWC321' );
+
+ select pwc321.task2_pljava();
+
+ and then to redeploy:
+
+ select sqlj.replace_jar( 'file:///tmp/PWC321-1.jar', 'PWC321', 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 java.util.*;
+import java.util.stream.*;
+import java.sql.SQLException;
+import java.util.logging.*;
+import java.sql.ResultSet;
+import java.sql.Date;
+
+public class Task1 {
+
+    private final static Logger logger = Logger.getAnonymousLogger();
+
+    @Function( schema = "pwc321",
+	       onNullInput = RETURNS_NULL,
+	       effects = IMMUTABLE )
+    public static final Float task1_pljava( int[] numbers ) throws SQLException {
+	logger.log( Level.INFO, "Entering pwc321.task1_pljava" );
+
+	if ( numbers.length % 2 != 0 )
+	    throw new SQLException( "Must be even in size" );
+
+	Float min_average = null;
+
+	List<Integer> sorted = IntStream.of( numbers ).boxed().collect( Collectors.toList() );
+	Collections.sort( sorted );
+
+	for ( int i = 0; i < sorted.size(); i++ ) {
+	    float current = ( sorted.get( i ) + sorted.get( sorted.size() - i - 1 ) ) / (float) 2;
+	    if ( min_average == null || current < min_average )
+		min_average = current;
+	}
+
+	return min_average;
+    }
+}