What is the difference between /* and /** pattern in Spring boot?

Question

I was trying to register certain URLs for a Filter when I noticed that there is a difference between /* and /** patte

Answer 1

IMHO code worths 100 words in this case:

import org.junit.Assert.assertFalse
import org.junit.Assert.assertTrue
import org.junit.Test
import org.springframework.util.AntPathMatcher

class AntPathMatcherTests {
    @Test
    fun twoAsterisks() {
        val pattern = "/api/balance/**"

        val matcher = AntPathMatcher()
        val matching = { path: String -> matcher.match(pattern, path) }

        assertTrue(matching("/api/balance"))
        assertTrue(matching("/api/balance/"))
        assertTrue(matching("/api/balance/abc"))
        assertTrue(matching("/api/balance/abc/"))
        assertTrue(matching("/api/balance/abc/update"))

        assertFalse(matching("/api/bala"))
    }

    @Test
    fun oneAsterisk() {
        val pattern = "/api/balance/*"

        val matcher = AntPathMatcher()
        val matching = { path: String -> matcher.match(pattern, path) }

        assertTrue(matching("/api/balance/"))
        assertTrue(matching("/api/balance/abc"))

        assertFalse(matching("/api/bala"))
        assertFalse(matching("/api/balance"))
        assertFalse(matching("/api/balance/abc/"))
        assertFalse(matching("/api/balance/abc/update"))
    }
}