JarCastingaleph-formatter
Aleph Formatter is a lightweight library for string formatting that supports both named and positional parameters with a twist: it has a limited support for object introspection.
installing
Historically, the library was found in jcenter(). But given jcenter()'s service end it was moved to maven central:
Maven:
<dependency>
<groupId>net.andreinc</groupId>
<artifactId>aleph</artifactId>
<version>0.1.1</version>
</dependency>
Gradle:
implementation 'net.andreinc:aleph:0.1.1'
benchmarks
Aleph Formatter performs better than String.format for simple cases. A jmh benchmark is showing the following results (smaller is better):
CPU: AMD Ryzen 7 5800x, PBO
Windows Version 10.0.19041 Build 19041
Benchmark (N) Mode Cnt Score Error Units
AlephFormatter.alephFormat 1 avgt 5 67.101 ± 2.103 ns/op
AlephFormatter.stringFormat 1 avgt 5 273.048 ± 5.632 ns/op
AlephFormatter.alephFormat 10 avgt 5 76.470 ± 4.423 ns/op
AlephFormatter.stringFormat 10 avgt 5 264.106 ± 3.018 ns/op
AlephFormatter.alephFormat 100 avgt 5 113.705 ± 5.941 ns/op
AlephFormatter.stringFormat 100 avgt 5 328.445 ± 15.986 ns/op
AlephFormatter.alephFormat 1000 avgt 5 257.674 ± 19.363 ns/op
AlephFormatter.stringFormat 1000 avgt 5 437.688 ± 11.813 ns/op
Source here.
Example - basic usage:
import static net.andreinc.aleph.AlephFormatter.str
//...
String s1 = str("#{1} #{0} #{1} #{0}", 1, 2)
.fmt();
System.out.println(s1);
Output:
2 1 2 1
Example - simple introspection
Each parameter supports limited method invocation:
String s2 = str("#{1}#{0.simpleName}", String.class, "Class:")
.fmt();
System.out.println(s2);
Output
Class:String
On the String.class you can invoke the method: getSimpleName directly in the template. String.class is the #{0} param.
Example - Named arguments
String s3 = str("#{date.dayOfMonth}-#{date.month}-#{date.year}")
.arg("date", LocalDate.now())
.fmt();
System.out.println(s3);
String s4 = str("#{2.simpleName}, #{1}, #{0}, #{aNumber}, #{anArray}", 1, "A", String.class)
.args("aNumber", 100, "anArray", new int[]{1,2,3,})
.fmt();
System.out.println(s4);
Output:
8-MAY-2018
String, A, 1, 100, [1, 2, 3]
Example - Escaping #{
String s5 = str("`#{escaped} #{notEscaped}").args("escaped", 1, "notEscaped", 2)
.fmt();
System.out.println(s5);
Output:
#{escaped} 2
Example - Changing Interpolation Styles
//Note the use of ${var} not #{var}
String s6 = str("${dollars}").args("dollars", "notPound")
.style(Styles.DOLLARS).fmt();
Output:
notPound