Prior to this commit, SpelParserConfiguration exposed 8 overloaded
constructors that accumulated over time as new configuration options
were introduced (auto-grow support since 3.0, maximumExpressionLength
in 5.2.25, maximumOperations in 6.2.19, and maximumBigPowerBits in
7.0.9), culminating in an 8-parameter constructor. This made call sites
hard to read due to unlabeled sequences of booleans and ints, and it
forced users who wanted to override a single setting to also supply
every other value explicitly.
To address that, this commit introduces a builder API in
SpelParserConfiguration, following the pattern already established by
SimpleEvaluationContext's builder API.
Specifically, SpelParserConfiguration.builder() returns a Builder that
is pre-populated with the same defaults as the no-arg constructor,
including the SpringProperties-driven overrides for the default
compiler mode, maximum operations, and maximum big-power bits -- the
latter two are only resolved lazily in build(), so that overriding them
via the builder never triggers an unnecessary SpringProperties lookup.
Each property has a dedicated, named setter (compilerMode(),
compilerClassLoader(), maximumAutoGrowSize(),
maximumExpressionLength(), maximumOperations(), maximumBigPowerBits()),
and the two auto-grow flags are exposed as simple no-arg opt-ins
(autoGrowNullReferences(), autoGrowCollections()) since they both
default to false. build() delegates to the existing canonical
constructor, so validation and defaults remain centralized in one
place.
In addition, a new SpelParserConfiguration.withDefaults() factory
method has been introduced as shorthand for
SpelParserConfiguration.builder().build(), for the common case where
none of the builder's defaults need to be overridden.
As the one deliberate exception to matching the no-arg constructor's
defaults, the builder defaults maximumAutoGrowSize to 256 -- aligned
with DataBinder.DEFAULT_AUTO_GROW_COLLECTION_LIMIT -- rather than the
constructors' Integer.MAX_VALUE. The constructors keep their legacy
default for backward compatibility, but the builder is a new, opt-in
API that is not bound by that compatibility contract.
This change is purely additive: none of the existing constructors have
been modified or deprecated. Deprecating those constructors in favor of
the builder is being deferred to 7.1, since new deprecations should not
be introduced in a patch release. In the meantime, the Javadoc for the
constructors and for the SPRING_EXPRESSION_*_PROPERTY_NAME constants
has been updated to favor the builder (or a specific Builder setter)
instead of the constructors, and the class-level Javadoc now states
that the constructors are planned to be deprecated in favor of the
builder as of Spring Framework 7.1.
SpelExpressionParser's no-arg constructor, ExpressionState's two
convenience constructors, and StandardBeanExpressionResolver's
ClassLoader-based constructor have all been switched from the
SpelParserConfiguration constructors to the builder (or
withDefaults()). This is behaviorally identical in every case:
autoGrowCollections remains false at each of those call sites, and
maximumAutoGrowSize -- the only property whose default differs between
the constructors and the builder -- has no effect when
autoGrowCollections is false.
Tests have been added in a new SpelParserConfigurationTests class to
verify that the builder's defaults match the no-arg constructor (with
the one intentional maximumAutoGrowSize exception called out above),
that custom values are applied correctly, and that invalid values are
rejected. The nested LegacyConstructorTests class provides regression
coverage for each of the legacy constructors, consolidating their usage
in tests to a single class -- which will keep any future deprecation
warnings confined to this class -- and documents that, unlike the
builder, the canonical constructor does not (yet) reject a negative
maximumAutoGrowSize. The remaining incidental usages of the
SpelParserConfiguration constructors throughout EvaluationTests,
IndexingTests, SpelCompilationCoverageTests, SpelReproTests, and
SpelCompilerTests have been converted to use the builder.
Furthermore, the reference documentation has been updated to recommend
the builder and withDefaults() over the constructors, both in prose and
in the Java/Kotlin examples.
Closes gh-37187
Prior to this commit, the SpelParserConfiguration constructors that
omit an explicit maximumAutoGrowSize left collection auto-growing
effectively unbounded, defaulting to Integer.MAX_VALUE. That default
was inconsistent with the auto-grow limit applied elsewhere in the
framework for data binding (see
DataBinder.DEFAULT_AUTO_GROW_COLLECTION_LIMIT).
To address that, this commit introduces a new
SpelParserConfiguration.DEFAULT_MAX_AUTO_GROW_SIZE constant (set to 256
to match DataBinder.DEFAULT_AUTO_GROW_COLLECTION_LIMIT) and switches
the constructors that previously hard-coded Integer.MAX_VALUE to use
this new default instead. Constructors that accept an explicit
maximumAutoGrowSize are unaffected.
In addition, SpelParserConfiguration now enforces that a user-supplied
maximumAutoGrowSize is not a negative value, consistent with the
preconditions already enforced for maximumExpressionLength,
maximumOperations, maximumBigPowerBits, and maximumNestingDepth. A
value of 0 remains supported (effectively disabling collection
auto-growing) and is now documented as such in the Javadoc.
The Spring Framework reference documentation has also been updated to
describe the new default, and tests have been added to IndexingTests to
verify the default, the ability to override it, and the new
precondition.
Closes gh-36995
This commit introduces support for limiting the structural nesting
depth of a SpEL expression during parsing. Without such a limit, an
expression with deeply nested constructs (for example, inline lists or
maps, parenthesized expressions, ternary or Elvis expressions, or
chained unary operators) can cause SpEL's recursive-descent parser to
throw a StackOverflowError which lacks useful diagnostics for
developer's attempting to assess what went wrong.
With this commit, a nesting-depth counter is now tracked around the
parser's primary recursive entry point (eatExpression()) as well as
around chained unary operators (eatUnaryExpression()), ensuring that
independent, sibling uses of assignment, Elvis, and ternary expressions
do not inadvertently accumulate depth and trip the limit.
If the configured (or default) nesting-depth limit is exceeded during
parsing, a SpelParseException is thrown instead, with a message that
reports the configured limit.
The limit can be configured on a per-use-case basis via
SpelParserConfiguration and defaults to 1000.
Closes gh-36723
Prior to this commit, some same-page links in our Antora-based docs
were written using the `xref:` macro, which Antora resolves as a
cross-page reference. However, a same-page target can be misread as a
page reference and break the site build (as nearly happened in
gh-37152), whereas `<<id,text>>` only ever resolves against the current
page's own anchors.
To address that inconsistency and avoid potential future bugs (broken
links), this commit converts all such same-page `xref:` links to
`<<id,text>>`, leaving genuine cross-page `xref:` links are unaffected.
Closes gh-37161
This commit introduces a configurable limit on the estimated result size
of BigDecimal and BigInteger power operations within SpEL expressions.
The estimated result size in bits is computed as the product of the base
value's bit length and the exponent. If this limit is exceeded, a
SpelEvaluationException is thrown.
The limit defaults to 1,000,000 bits, which is approximately equivalent
to a decimal number with 300,000 digits, and can be configured either
on a per-use-case basis via the new maximumBigPowerBits constructor
argument in SpelParserConfiguration or globally as a JVM system
property or Spring property named `spring.expression.maxBigPowerBits`.
Parsers intended for trusted internal expressions may supply
Integer.MAX_VALUE to remove the limit entirely.
Closes ch-37034
This commit introduces a configurable limit on the estimated result size
of BigDecimal and BigInteger power operations within SpEL expressions.
The estimated result size in bits is computed as the product of the base
value's bit length and the exponent. If this limit is exceeded, a
SpelEvaluationException is thrown.
The limit defaults to 1,000,000 bits, which is approximately equivalent
to a decimal number with 300,000 digits, and can be configured either
on a per-use-case basis via the new maximumBigPowerBits constructor
argument in SpelParserConfiguration or globally as a JVM system
property or Spring property named `spring.expression.maxBigPowerBits`.
Parsers intended for trusted internal expressions may supply
Integer.MAX_VALUE to remove the limit entirely.
Closes ch-37034
A user reported confusion between two distinct uses of "wraps" in the
AOP proxy documentation for Bean Overrides: the sense in which a
Mockito spy wraps the original bean instance it was created from, and
the sense in which a Spring AOP proxy wraps the spy in the actual
object graph.
To address that, this commit adds two small diagrams to the general
"Bean Overrides and Spring AOP Proxies" section, illustrating, from a
caller's perspective, the shape of the bean for the
REPLACE/REPLACE_OR_CREATE strategy (no proxy at all) versus the WRAP
strategy (an AOP proxy still created, now wrapping the override
instance instead of the original bean). Both diagrams use the same
generic "override instance" label, since the section is not specific to
Mockito; a Mockito spy created by @MockitoSpyBean is mentioned only as
an example.
The accompanying text is revised to reserve "wraps" for the AOP proxy
relationship and to explicitly call out that a Mockito spy's
relationship to its original bean instance is a separate concern from
AOP proxy nesting.
The @MockitoSpyBean-specific strategy paragraph in the
@MockitoBean/@MockitoSpyBean documentation has also been revised
similarly, and now points to the new diagram.
See gh-37121
This commit documents how the Bean Override support in the TestContext
framework interacts with Spring AOP proxies created for annotations
such as @Transactional, @Cacheable, and @Retryable.
The new "Bean Overrides and Spring AOP Proxies" section in the general
Bean Overriding documentation explains that overrides using the WRAP
strategy (such as @MockitoSpyBean) end up as the target of any AOP
proxy subsequently created for the original bean; whereas, overrides
using the REPLACE or REPLACE_OR_CREATE strategy (such as @TestBean,
@MockitoBean) bypass the container's bean post-processing entirely and
therefore carry no AOP advice at all.
The new "@MockitoSpyBean and Spring AOP Proxies" section documents the
resulting stubbing and verification semantics. Verification via
Mockito's verify() API works transparently regardless of whether it is
invoked on the proxy or on the spy. Stubbing via doReturn(...)/doThrow(...)
is safe for stateless advice such as @Retryable, but can silently
corrupt the spy's configured answers for stateful or memoizing advice
such as @Cacheable, since the invocation used to declare a stub is
intercepted by Mockito before it reaches the spy and returns an empty
value that such advice may then cache.
AopTestUtils.getUltimateTargetObject(...) is documented as the way to
stub directly against the spy in that case.
The same section also documents how to disable the AOP advice for a
test altogether while leaving it in place in production code – for
example, binding a @Retryable attribute to a property placeholder
overridden via @TestPropertySource, or replacing the CacheManager with
a NoOpCacheManager via @TestBean.
Brief cross-referencing notes have also been added to the @TestBean
documentation and to the existing AopTestUtils description in the
"General Testing Utilities" section, to avoid duplicating the
explanation across pages.
In addition, the Javadoc for @MockitoSpyBean now contains a concise
WARNING summarizing these AOP proxy implications and linking to the new
reference documentation section for details.
Closes gh-37121
Property accessors resolved via SpEL's ReflectivePropertyAccessor and
DataBindingPropertyAccessor may be JavaBean-style accessors or plain
accessor methods used to support data classes such as Java records and
Kotlin data classes. However, neither accessor can determine, via
reflection, whether such a method is a side-effect-free read or an
action that happens to return a value. For example, File.delete() is a
public method that returns a boolean and therefore looks like a
plain "property".
To better inform users, this commit updates the Javadoc for
ReflectivePropertyAccessor, DataBindingPropertyAccessor, and
SimpleEvaluationContext (as well as in the SpEL reference
documentation) to clarify that restricting a SimpleEvaluationContext to
read-only data binding governs only whether assignment to a property is
permitted and does not guarantee that reading a property is free of
side effects. The reference documentation's "Security Considerations"
section now also defines what makes a method "accessor-shaped", with
concrete examples of safe versus side-effecting methods that share that
shape (for example, File.delete(), Queue.poll(), and
AtomicInteger.incrementAndGet()).
Building on that clarification, this commit introduces a new "Object
Design" section to the SpEL reference documentation, analogous to the
"Model Design" guidance for web data binding. This new section
recommends that any object reachable from an untrusted SpEL expression
(not only the root object) be a purpose-built, immutable type with a
deliberately limited surface area, and that its accessor-shaped methods
be audited for unsafe side effects. The new section also notes that
reachability is transitive through both property navigation and
indexing (for example, rootObject.child.grandchild or
rootObject.items[0]).
In any case, it remains the responsibility of the code that exposes a
root object or other reachable object to an expression from an
untrusted source to ensure that none of its accessor-shaped methods
perform an unsafe action.
Closes gh-37102
This commit adds a "Lifecycle and Reuse" section to the SpEL reference
documentation, immediately following the security considerations
introduced for gh-36997, explaining that AST nodes within a parsed
Expression may cache resolved PropertyAccessor, IndexAccessor,
MethodExecutor, and ConstructorExecutor instances for performance.
We also now document that reusing a parsed Expression across
EvaluationContext instances of the same type and with equivalent
configuration is supported (even if atypical), including when accessors
or resolvers registered with a context change between evaluations, but
that reusing a parsed Expression across contexts with different
security implications (for example, first against a
StandardEvaluationContext and later against a SimpleEvaluationContext)
is not supported, since cached state from a more permissive evaluation
may be reused during a more restrictive one.
The Javadoc for Expression, SpelExpression, EvaluationContext,
StandardEvaluationContext, SimpleEvaluationContext, PropertyAccessor,
IndexAccessor, MethodExecutor, and ConstructorExecutor has also been
updated to make these contracts discoverable via the API as well.
Closes gh-36968
This commit clarifies in the Javadoc for EvaluationContext,
StandardEvaluationContext, and SimpleEvaluationContext (as well as in
the SpEL reference documentation) that StandardEvaluationContext must
never be used to evaluate expressions from an untrusted source, and
that SimpleEvaluationContext's restricted language and feature subset
is only a best-effort measure. The updated documentation also defines a
"trusted" source as a developer or administrator of the application and
points out that it is the responsibility of the code that configures an
EvaluationContext to ensure that no object reachable via the context
exposes dangerous operations.
Closes gh-36997
This commit introduces support for tracking operations during SpEL
expression evaluation. If the maximum number of operations is exceeded,
a SpelEvaluationException is thrown.
The limit can be configured either on a per-use-case basis via
SpelParserConfiguration supplied to the SpelExpressionParser or
globally as a JVM system property or Spring property named
`spring.expression.maxOperations`.
Closes gh-36801
The links to docs.seleniumhq.org no longer resolve, since the host was
retired.
This commit changes those links to use the current Selenium
documentation at selenium.dev.
Closes gh-36875
Signed-off-by: leestana01 <leestana01@naver.com>
Prior to this commit, the `antora` Gradle task silently failed to build
the reference documentation, since Antora uses the latest LTS release
for Node.js by default, and the latest LTS apparently does not work for
us.
Sam Brannen
Brian Clozel
Gabriel Gerhardt
Hyunwoo Jung
rstoyanchev
jhan0121
Yanming Zhou
leestana01
Dennis-Mircea Ciupitu
dependabot[bot]