return validators
}

// addIPv6Checks adds IPv6 related checks
func addIPv6Checks(checks []Checker) []Checker {
	checks = append(checks,
		FileContentCheck{Path: ipv6DefaultForwarding, Content: []byte{'1'}},
	)
	return checks
}

// addIPv4Checks adds IPv4 related checks
func addIPv4Checks(checks []Checker) []Checker {
	checks = append(checks,
		FileContentCheck{Path: ipv4Forward, Content: []byte{'1'}})
	return checks

    @Test
    void testMatchesVersion() {
        MavenPluginJavaPrerequisiteChecker checker = new MavenPluginJavaPrerequisiteChecker(new GenericVersionScheme());
        assertTrue(checker.matchesVersion("1.0", "1.8"));
        assertTrue(checker.matchesVersion("1.8", "9.0.1+11"));
        assertFalse(checker.matchesVersion("[1.0,2],[3,4]", "2.1"));
        assertTrue(checker.matchesVersion("[1.0,2],[3,4]", "3.1"));

      checkElementsNotNull(elements, n);
      getReadyToExpandTo(size + n);
      /*
       * The following call is not statically checked, since arraycopy accepts plain Object for its
       * parameters. If it were statically checked, the checker would still be OK with it, since
       * we're copying into a `contents` array whose type allows it to contain nulls. Still, it's

import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * An immutable sorted set with one or more elements. TODO(jlevy): Consider separate class for a
 * single-element sorted set.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 */

		}
		netLimitSem <- struct{}{}
		hasToken = true
	}

	checker := new(netTokenChecker)
	runtime.SetFinalizer(checker, (*netTokenChecker).panicUnreleased)

	return func() {
		if checker.released {
			panic("internal error: net token released twice")
		}
		checker.released = true
		if hasToken {
			<-netLimitSem
		}
		runtime.SetFinalizer(checker, nil)
	}, nil
}

var (
	netLimitOnce sync.Once

## Use the instance as a dependency

Then, we could use this `checker` in a `Depends(checker)`, instead of `Depends(FixedContentQueryChecker)`, because the dependency is the instance, `checker`, not the class itself.

And when solving the dependency, **FastAPI** will call this `checker` like:

```Python
checker(q="somequery")
```

```Python hl_lines="16"
{!../../../docs_src/dependencies/tutorial011.py!}
```

这样就可以**参数化**依赖项，它包含 `checker.fixed_content` 的属性 - `"bar"`。

## 把实例作为依赖项

然后，不要再在 `Depends(checker)` 中使用 `Depends(FixedContentQueryChecker)`， 而是要使用 `checker`，因为依赖项是类实例 - `checker`，不是类。

处理依赖项时，**FastAPI** 以如下方式调用 `checker`：

```Python
checker(q="somequery")
```

……并用*路径操作函数*的参数 `fixed_content_included` 返回依赖项的值：

```Python hl_lines="20"

	finalSwitchCase
	inTypeSwitch
)

func (check *Checker) simpleStmt(s ast.Stmt) {
	if s != nil {
		check.stmt(0, s)
	}
}

func trimTrailingEmptyStmts(list []ast.Stmt) []ast.Stmt {
	for i := len(list); i > 0; i-- {
		if _, ok := list[i-1].(*ast.EmptyStmt); !ok {
			return list[:i]
		}
	}
	return nil
}

func (check *Checker) stmtList(ctxt stmtContext, list []ast.Stmt) {

		t.Fatalf("typechecking runtime failed: %v", err)
	}

	// Analyze all atomic.*64 callsites.
	v := Visitor{t: t, fset: fset, types: info.Types, checked: checked}
	ast.Walk(&v, pkg)
}

type Visitor struct {
	fset    *token.FileSet
	types   map[ast.Expr]types.TypeAndValue
	checked map[string]bool
	t       *testing.T
}

func (v *Visitor) Visit(n ast.Node) ast.Visitor {
	c, ok := n.(*ast.CallExpr)
	if !ok {

          "version": {
            "requires": "${jsr305.version}"
          }
        },
        {
          "group": "org.checkerframework",
          "module": "checker-qual",
          "version": {
            "requires": "${checker.version}"
          }
        },
        {
          "group": "com.google.errorprone",
          "module": "error_prone_annotations",
          "version": {