/**
     * Gets a map of filtered environment variables.
     *
     * @param keyPattern The pattern to filter environment variable keys.
     * @return A map of filtered environment variables.
     */
    public Map<String, String> getFilteredEnvMap(final String keyPattern) {
        final Pattern pattern = Pattern.compile(keyPattern);
        return getEnvMap().entrySet().stream().filter(e -> {

    // different from each other. If buildKeepingLast() collapsed duplicates, that might end up not
    // being true.
    Pattern pattern = Pattern.compile("Multiple entries with same key: four=(.*) and four=(.*)");
    assertThat(expected).hasMessageThat().matches(pattern);
    Matcher matcher = pattern.matcher(expected.getMessage());
    assertThat(matcher.matches()).isTrue();
    assertThat(matcher.group(1)).isNotEqualTo(matcher.group(2));

You can define a <abbr title="A regular expression, regex or regexp is a sequence of characters that define a search pattern for strings.">regular expression</abbr> `pattern` that the parameter should match:

{* ../../docs_src/query_params_str_validations/tutorial004_an_py310.py hl[11] *}

This specific regular expression pattern checks that the received parameter value:

* `^`: starts with the following characters, doesn't have characters before.

        }

        assertEquals(threadCount * opsPerThread, successCount.get(), "All operations should succeed");
    }

    /**
     * Test that session release with double-check pattern prevents race conditions.
     */
    @Test
    public void testSessionReleaseDoubleCheckPattern() throws Exception {
        // Given

	rulesCase7.Add(NewPattern("", "*.jpg"), TargetID{"1", "webhook"})

	rulesCase8 := make(Rules)
	rulesCase8.Add(NewPattern("2010*", ""), TargetID{"1", "webhook"})

	testCases := []struct {
		rules          Rules
		pattern        string
		targetID       TargetID
		expectedResult int
	}{
		{rulesCase1, NewPattern("*", ""), TargetID{"1", "webhook"}, 1},
		{rulesCase2, NewPattern("*", ""), TargetID{"2", "amqp"}, 2},

	}

	if prefix == "" {
		return true
	}
	if v.ExcludeFolders && strings.HasSuffix(prefix, "/") {
		return false
	}

	for _, sprefix := range v.ExcludedPrefixes {
		// Note: all excluded prefix patterns end with `/` (See Validate)
		sprefix.Prefix += "*"

		if matched := wildcard.MatchSimple(sprefix.Prefix, prefix); matched {
			return false
		}
	}
	return true
}

            title="Query string",
            description="Query string for the items to search in the database that have a good match",
            min_length=3,
            max_length=50,
            pattern="^fixedquery$",
            deprecated=True,
        ),
    ] = None,
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

        alias="item-query",
        title="Query string",
        description="Query string for the items to search in the database that have a good match",
        min_length=3,
        max_length=50,
        pattern="^fixedquery$",
        deprecated=True,
    ),
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

        // Prepare test data - 24 bytes for resume key + 4 bytes for context length
        byte[] buffer = new byte[28];

        // Fill resume key with test pattern
        for (int i = 0; i < 24; i++) {
            buffer[i] = (byte) (i + 1);
        }

        // Add context length (reserved) - 4 bytes
        buffer[24] = 0x00;
        buffer[25] = 0x00;

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: str | None = Query(
        default=None, min_length=3, max_length=50, pattern="^fixedquery$"
    ),
):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})