* @since 3.8.1
     **/
    void setBlocked(boolean blocked);

    //
    // New interface methods for the repository system.
    //
    /**
     *
     * @param artifact an artifact
     * @return found artifact
     * @since 3.0-alpha-3
     */
    Artifact find(Artifact artifact);

    /**
     * Finds the versions of the specified artifact that are available in this repository.
     *

    }

    /**
     * Retrieves a specific group by its ID and applies LDAP manager settings.
     *
     * @param id the unique identifier of the group
     * @return an OptionalEntity containing the group if found, empty otherwise
     */
    public OptionalEntity<Group> getGroup(final String id) {
        return groupBhv.selectByPK(id).map(g -> {
            ComponentUtil.getLdapManager().apply(g);
            return g;
        });

    }

    @Test
    public void test_differentCauseTypes() {
        // Test with different types of causes
        StorageException exception1 = new StorageException("IO Error", new java.io.IOException("File not found"));
        assertTrue(exception1.getCause() instanceof java.io.IOException);

        StorageException exception2 = new StorageException("NPE", new NullPointerException("Null reference"));

                .filter(l -> l.startsWith("distributionUrl"))
                .findFirst()
                .orElseThrow(() -> new IllegalStateException("distributionUrl not found in " + props));

        int idx = distributionUrl.indexOf('=');
        if (idx < 0) {
            throw new IllegalStateException("Malformed distributionUrl line: " + distributionUrl);
        }

     * is queried frequently and exceptions would be rather costly to
     * throw on a regular basis here.
     *
     * @param host the hostname to resolve
     * @return the resolved NbtAddress or null if not found
     */

    public synchronized static NbtAddress getByName(final String host) {
        return getByName(new Name(host, 0x20, null));
    }

    synchronized static NbtAddress getByName(final Name name) {

* **`400 - 499`** are for "Client error" responses. These are the second type you would probably use the most.
    * An example is `404`, for a "Not Found" response.
    * For generic errors from the client, you can just use `400`.

- 客户端没有访问该资源的权限
- 客户端要访问的项目不存在
- 等等

遇到这些情况时，通常要返回 **4XX**（400 至 499）**HTTP 状态码**。

这与表示请求成功的 **2XX**（200 至 299）HTTP 状态码类似。那些“200”状态码表示某种程度上的“成功”。

而 **4XX** 状态码表示客户端发生了错误。

大家都知道**「404 Not Found」**错误，还有调侃这个错误的笑话吧？

## 使用 `HTTPException` { #use-httpexception }

向客户端返回 HTTP 错误响应，可以使用 `HTTPException`。

### 导入 `HTTPException` { #import-httpexception }

// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package tar

import (
	"bytes"
	"fmt"
	"strconv"
	"strings"
	"time"
)

// hasNUL reports whether the NUL character exists within s.
func hasNUL(s string) bool {
	return strings.Contains(s, "\x00")
}

// isASCII reports whether the input is an ASCII C-style string.

        return "form";
    }

    /**
     * Gets the parameter value for the specified name.
     * @param name The parameter name.
     * @return The parameter value, or null if not found.
     */
    public String getParameter(final String name) {
        return parameterMap.get(name);
    }

    @Override
    public String getRealm() {
        return null;
    }

        PreauthIntegrityContext context = sessionContexts.get(sessionId);
        if (context == null) {
            if (enforceIntegrity) {
                throw new CIFSException("No preauth integrity context found for session: " + sessionId);
            }
            log.warn("No preauth integrity context for session {}, skipping update", sessionId);
            return;
        }

        if (!context.isValid()) {