Interface ResultChecker

All Superinterfaces:

Consumer<ScriptResult>

public interface ResultChecker
extends Consumer<ScriptResult>

A checker for ScriptResults that imposes some set of requirements that must be satisfied.

By convention, instances should throw a ResultCheckerException (or some subtype) if a requirement is not met, specifying a specific SnippetOutcome (by its index) if appropriate.

See Also:

• JavaBox.execute()

Method Summary

Modifier and Type	Method	Description
static ResultChecker	allSuccessful()	Create an instance that verifies that all SnippetOutcomes are successful.
default void	check(ScriptResult result)	Apply this instance to the given result.
static ResultChecker	checkSnippets(BiConsumer<? super ScriptResult, ? super Integer> snippetChecker)	Create an instance that verifies that every SnippetOutcomes meets some requirement.
static ResultChecker	returns(Class<?> type, boolean allowNull)	Create an instance that verifies that the last SnippetOutcome was a successful expression returning a value having the specified type.

Methods inherited from interface java.util.function.Consumer

accept, andThen

Method Details

check

default void check(ScriptResult result)

Apply this instance to the given result.

This method is a synonym for accept().

Throws:

IllegalArgumentException - if a requirement is violated

allSuccessful

static ResultChecker allSuccessful()

Create an instance that verifies that all SnippetOutcomes are successful.

This just checks every SnippetOutcome is an instance of SnippetOutcome.Successful.

checkSnippets

static ResultChecker checkSnippets(BiConsumer<? super ScriptResult, ? super Integer> snippetChecker)

Create an instance that verifies that every SnippetOutcomes meets some requirement.

The snippetChecker will be invoked with the index of each SnippetOutcome. It should throw ResultCheckerException using its given parameters if the corresponding SnippetOutcome fails to meet the requirement.

Parameters:

snippetChecker - checks each SnippetOutcome

Throws:

IllegalArgumentException - if snippetChecker is null

returns

static ResultChecker returns(Class<?> type,
 boolean allowNull)

Create an instance that verifies that the last SnippetOutcome was a successful expression returning a value having the specified type.

This is useful in scenarios where the purpose of the script is to produce some result. This checks that:

• The script was not empty, i.e., it contained at least one snippet
• Every snippet in the script was successful
• The final snippet was an expression having the specified type
• If allowNull is false, the returned value is not null

If the above criteria are not met, a ResultCheckerException is thrown.

Parameters:

type - expected return type

allowNull - true to allow null values, otherwise false

Throws:

IllegalArgumentException - if type is null or primitive