1. Design pattern name : Factory method pattern

2. Design pattern object : QrSegment,
MakeAlphaNumericToSegment,MakeBytesToSegment,  MakeNumericToSegment
3. reason : function to make segment is changed by kind of string. And
there is possible to add function to make segment.

4. explanation :
product : MakeSegment,
concrete product : MakeBytesToSegment, MakeNumericToSegment,
MakeAlphaNumericToSegment
creator : QrSegmentTo
concrete creator : MakeSegmentFactory

java/src/main/java/io/nayuki/qrcodegen/MakeSegment.java

@@ -0,0 +1,4 @@
+
+public interface MakeSegment {
+	public QrSegment excute(String text);
+}

java/src/main/java/io/nayuki/qrcodegen/MakeSegmentFactory.java

@@ -0,0 +1,15 @@
+public class MakeSegmentFactory {
+	public static MakeSegment getMakeSegment(String text) {
+		MakeSegment makeSegment = null;
+		
+		if (text.equals(""));  // Leave result empty
+		else if (QrSegment.NUMERIC_REGEX.matcher(text).matches())
+			makeSegment = new MakeNumericToSegment();
+		else if (QrSegment.ALPHANUMERIC_REGEX.matcher(text).matches())
+			makeSegment = new MakeAlphaNumericToSegment();
+		else
+			makeSegment = new MakeBytesToSegment();
+		
+		return makeSegment;
+	}
+}

java/src/main/java/io/nayuki/qrcodegen/QrSegment.java

@@ -71,7 +71,17 @@ public final class QrSegment {
 		return segments;
 	}
 	
+	public static List<QrSegment> makeSegments(String text) {
+		Objects.requireNonNull(text);
+		// Select the most efficient segment encoding automatically
+		List<QrSegment> segments = new ArrayList<>();
+			
+		MakeSegment makeSegment = MakeSegmentFactory.getMakeSegment(text);
+		
+		segments.add(makeSegment.excute(text));
 	
+		return segments;
+	}
 	/**
 	 * Returns a segment representing an Extended Channel Interpretation
 	 * (ECI) designator with the specified assignment value.