<name>Maven Integration Test :: it0063</name>
  <description>Test the use of a system scoped dependency to a (fake) tools.jar.</description>

  <dependencies>
    <dependency>
      <groupId>com.sun</groupId>
      <artifactId>tools</artifactId>
      <version>1.4.2</version>
      <scope>system</scope>
      <systemPath>${jre.home}/../lib/tools.jar</systemPath>
    </dependency>
  </dependencies>

     * {@return all enabled sources that provide files in the given language for the given scope}.
     * If the given scope is {@code null}, then this method returns the enabled sources for all scopes.
     * If the given language is {@code null}, then this method returns the enabled sources for all languages.
     * An arbitrary number of source roots may exist for the same scope and language.
     * It may be, for example, the case of a multi-versions project.

                        },
                        "username": {"title": "Username", "type": "string"},
                        "password": {"title": "Password", "type": "string"},
                        "scope": {"title": "Scope", "type": "string", "default": ""},
                        "client_id": {
                            "title": "Client Id",
                            "anyOf": [{"type": "string"}, {"type": "null"}],

                        },
                        "username": {"title": "Username", "type": "string"},
                        "password": {"title": "Password", "type": "string"},
                        "scope": {"title": "Scope", "type": "string", "default": ""},
                        "client_id": {
                            "title": "Client Id",
                            "anyOf": [{"type": "string"}, {"type": "null"}],

            String type,
            String classifier,
            String scope,
            String inheritedScope,
            boolean optional) {
        String desiredScope = Artifact.SCOPE_RUNTIME;

        if (inheritedScope == null) {
            desiredScope = scope;
        } else if (Artifact.SCOPE_TEST.equals(scope) || Artifact.SCOPE_PROVIDED.equals(scope)) {
            return null;

	scopes := db.Statement.scopes
	db.Statement.scopes = nil
	for _, scope := range scopes {
		db = scope(db)
	}
	return db
}

// Preload preload associations with given conditions
//
//	// get all users, and preload all non-cancelled orders
//	db.Preload("Orders", "state NOT IN (?)", "cancelled").Find(&users)
func (db *DB) Preload(query string, args ...interface{}) (tx *DB) {
	tx = db.getInstance()

                    && a.getArtifactId().equals("tools")) {
                // The system scoped dependencies will be present in the classloader for the plugin
                return;
            }
        }

        fail("Can't find the system scoped dependency in the plugin artifacts.");
    }

                            "title": "Password",
                            "type": "string",
                            "format": "password",
                        },
                        "scope": {"title": "Scope", "type": "string", "default": ""},
                        "client_id": {
                            "title": "Client Id",
                            "anyOf": [{"type": "string"}, {"type": "null"}],

import org.eclipse.aether.impl.scope.InternalScopeManager;
import org.eclipse.aether.internal.impl.scope.ManagedDependencyContextRefiner;
import org.eclipse.aether.internal.impl.scope.ManagedScopeDeriver;
import org.eclipse.aether.internal.impl.scope.ManagedScopeSelector;
import org.eclipse.aether.internal.impl.scope.OptionalDependencySelector;
import org.eclipse.aether.internal.impl.scope.ScopeDependencySelector;

但由于这种用例很常见，FastAPI 为了简便，就直接提供了对它的支持。

///

### 使用表单数据

/// tip | 提示

`OAuth2PasswordRequestForm` 类依赖项的实例没有以空格分隔的长字符串属性 `scope`，但它支持 `scopes` 属性，由已发送的 scope 字符串列表组成。

本例没有使用 `scopes`，但开发者也可以根据需要使用该属性。

///

现在，即可使用表单字段 `username`，从（伪）数据库中获取用户数据。

如果不存在指定用户，则返回错误消息，提示**用户名或密码错误**。

本例使用 `HTTPException` 异常显示此错误：