This commit moves findPublicDeclaringClass() from ReflectionHelper to
CodeFlow, since findPublicDeclaringClass() is only used for bytecode
generation and therefore not for reflection-based invocations.
It was never necessary for SpEL's OptimalPropertyAccessor to be public.
Instead, clients should interact with OptimalPropertyAccessor
exclusively via the CompilablePropertyAccessor API.
In light of that, this commit makes SpEL's OptimalPropertyAccessor
private.
Closes gh-32410
Commit c79436f832 ensured that methods are invoked via a public
interface or public superclass when compiling Spring Expression
Language (SpEL) expressions involving method references or property
access (see MethodReference, PropertyOrFieldReference, and
collaborating support classes). However, compilation of expressions
that access properties by indexing into an object by property name is
still not properly supported in all scenarios.
To address those remaining use cases, this commit ensures that methods
are invoked via a public interface or public superclass when accessing
a property by indexing into an object by the property name – for
example, `person['name']` instead of `person.name`.
In addition, SpEL's Indexer now properly relies on the
CompilablePropertyAccessor abstraction instead of hard-coding support
for only OptimalPropertyAccessor. This greatly reduces the complexity
of the Indexer and simultaneously allows the Indexer to potentially
support other CompilablePropertyAccessor implementations.
Closes gh-29857
Although the Spring Expression Language (SpEL) generally does a good
job of locating the public declaring class or interface on which to
invoke a method in a compiled expression, prior to this commit there
were still a few unsupported use cases.
To address those remaining use cases, this commit ensures that methods
are invoked via a public interface or public superclass whenever
possible when compiling SpEL expressions.
See gh-29857
Prior to this commit, if a Spring Expression Language (SpEL) expression
referenced the root context object via the #root or #this variable, we
inserted a checkcast in the generated byte code that cast the object to
its concrete type. However if the root context object's type was
non-public, that resulted in an IllegalAccessError when the compiled
byte code was executed.
VariableReference.getValueInternal() already contains a solution for
global variables which inserts a checkcast to Object in the generated
byte code instead of to the object's concrete non-public type.
This commit therefore applies the same logic to #root (or #this when
used to reference the root context object) that is already applied to
global variables.
Closes gh-32356
Prior to this commit, the reference manual only documented indexing
support for arrays, lists, and maps.
This commit improves the overall documentation for SpEL's property
navigation and indexing support and introduces additional documentation
for indexing into Strings and Objects.
Closes gh-32355
Since the Spring Expression Language does not actually support local
variables in expressions, this commit deprecates all public APIs
related to local variables in ExpressionState (namely, the two
enterScope(...) variants that accept local variable data,
setLocalVariable(), and lookupLocalVariable()).
In addition, we no longer invoke `state.enterScope("index", ...)` in
the Projection and Selection AST nodes since the $index local variable
was never accessible within expressions anyway.
See gh-23202
Closes gh-32004
Although EvaluationContext defines the API for setting and looking up
variables, the internals of the Spring Expression Language (SpEL)
actually provide explicit support for registering functions as
variables.
This is self-evident in the two registerFunction() variants in
StandardEvaluationContext; however, functions can also be registered as
variables when using the SimpleEvaluationContext.
Since custom functions are also viable in use cases involving the
SimpleEvaluationContext, this commit documents that functions may be
registered in a SimpleEvaluationContext via setVariable().
This commit also explicitly documents the "function as a variable"
behavior in the class-level Javadoc for both StandardEvaluationContext
and SimpleEvaluationContext, as well as in the reference manual.
Closes gh-32258
To improve consistency and avoid confusion regarding primitive types
and their wrapper types, this commit ensures that we always use class
literals for primitive types.
For example, instead of using the `Void.TYPE` constant, we now
consistently use `void.class`.
Prior to this commit, SpEL's Indexer incorrectly requested conversion
to wrappers instead of primitives when setting an element in a
primitive array.
This commit addresses this by requesting primitive conversion -- for
example, conversion to `int.class` instead of `Integer.class` when
setting a value in an `int[]` array.
For greater clarity, this commit also switches from using `TYPE`
constants in wrapper classes to primitive class literals -- for
example, from `Integer.TYPE` to `int.class`.
Closes gh-32147
Since SpEL is no longer "in progress", this commit removes the obsolete
InProgressTests class and moves all non-duplicated test cases to other
test classes.
Prior to this commit, only the MethodFilter and ConstructorResolver
functional SPIs in the org.springframework.expression package were
annotated with @FunctionalInterface.
For consistency, this commit designates each of the following
functional SPIs in that package as a @FunctionalInterface as well.
- BeanResolver
- ConstructorExecutor
- MethodExecutor
- MethodResolver
Closes gh-32135
This commit introduces support for a Spring property named
`spring.context.expression.maxLength`. When set, the value of that
property is used internally in StandardBeanExpressionResolver to
configure the SpelParserConfiguration used when evaluating String
values in bean definitions, @Value, etc.
Closes gh-31952
Search for : assertThat\((.+).isEmpty\(\)\).isTrue\(\)
Replace with : assertThat($1).isEmpty()
Search for : assertThat\((.+).isEmpty\(\)\).isFalse\(\)
Replace with : assertThat($1).isNotEmpty()
Closes gh-31758
Search for : assertThat\((.+)\.equals\((\w+)\)\)\.isTrue\(\)
Replace with : assertThat($1).isEqualTo($2)
Search for : assertThat\((.+)\.equals\((\w+)\)\)\.isFalse\(\)
Replace with : assertThat($1).isNotEqualTo($2)
Closes gh-31763
This commit makes sure that the per-operation execution context for
caching and event listening does not recreate the default internal
delegates, but rather get initialized with a shared state.
This reduces the number of instances created per operation execution,
reducing the GC pressure as a result. This also makes sure that any
cache, such as the one in StandardTypeLocator, is reused.
Closes gh-31617
Due to the changes in gh-31341, if the repeat count in a SpEL
expression (using the repeat operator '*') is negative, we throw a
SpelEvaluationException with the MAX_REPEATED_TEXT_SIZE_EXCEEDED
message which is incorrect and misleading.
Prior to gh-31341, a negative repeat count resulted in an
IllegalArgumentException being thrown by String#repeat(), which was
acceptable in terms of diagnostics, but that did not make it
immediately clear to the user what the underlying cause was.
In light of the above, this commit improves diagnostics for a negative
repeated text count in SpEL expressions by throwing a
SpelEvaluationException with a new NEGATIVE_REPEATED_TEXT_COUNT error
message.
Closes gh-31342
If the resulting size of repeated text in a SpEL expression (using the
repeat operator '*') would exceed MAX_REPEATED_TEXT_SIZE, we currently
throw a SpelEvaluationException with the
MAX_REPEATED_TEXT_SIZE_EXCEEDED message.
However, if the calculation of the repeated text size results in
integer overflow, our max size check fails to detect that, and
String#repeat(int) throws a preemptive OutOfMemoryError from which the
application immediately recovers.
To improve diagnostics for users, this commit ensures that we
consistently throw a SpelEvaluationException with the
MAX_REPEATED_TEXT_SIZE_EXCEEDED message when integer overflow occurs.
Closes gh-31341
Prior to this commit the Spring Expression Language (SpEL) was able to
properly parse an expression that uses the safe navigation operator
(?.) with a method that has a `void` return type (for example,
"myObject?.doSomething()"); however, SpEL was not able to evaluate or
compile such expressions.
This commit addresses the evaluation issue by selectively not boxing
the exit type descriptor (for inclusion in the generated bytecode) when
the method's return type is `void`.
This commit addresses the compilation issue by pushing a null object
reference onto the stack in the generated byte code when the method's
return type is `void`.
Closes gh-27421
Prior to this commit, if a Spring Expression Language (SpEL) expression
contained property, field, or method references using the null-safe
navigation operator (?.), the generated AST String representation
incorrectly omitted the '?' characters.
For example, 'myProperty?.myMethod()' had a generated AST string
representation of 'myProperty.myMethod()'.
This commit addresses this by introducing isNullSafe() in
MethodReference and reworking the logic in
CompoundExpression.toStringAST().
Closes gh-31326
This commit revises the contribution for gh-25921 in the following ways.
- Use instanceof pattern matching
- Use List.of() and Map.of()
- Add missing @since tags
- Polish Javadoc
- Rename isNegativeNumber() to isNegativeNumberLiteral()
- Restructure InlineCollectionTests using @Nested, etc.
- Fix testListWithVariableNotCached() test: it previously set a SpEL
"variable" but tested a "property" in the root context object, which
effectively did not test anything.
- Introduce additional tests: listWithPropertyAccessIsNotCached(),
mapWithVariableIsNotCached(), and mapWithPropertyAccessIsNotCached().
Prior to this commit, it was unclear to users and third parties that it
is necessary to manually configure a StandardTypeLocator with a
specific ClassLoader to ensure that the SpEL expression parser is able
to reliably locate user types.
For example, the StandardBeanExpressionResolver in the spring-context
module configures a StandardTypeLocator using the bean ClassLoader of
the corresponding BeanFactory.
This commit improves the documentation to raise awareness of this fact.
Closes gh-26253
This commit adds support for inlined Kotlin value
class properties in SpEL by leveraging Kotlin
reflection instead of Java reflection broken
by the mangled method name.
Closes gh-30468
Java 12 introduced java.lang.Class#componentType() as a shortcut for
getComponentType().
Since we started using arrayType() in fe5560400c, this commit switches
to componentType() for consistent API usage style.
Prior to this commit, if a Spring Expression Language (SpEL) expression
contained indexed access to an object, the generated AST String
representation incorrectly included a dot ('.') before the index access.
For example, 'property[0]' had a generated AST string representation of
'property.[0]'.
This commit addresses this by reworking the logic in
CompoundExpression.toStringAST().
Closes gh-30610
Prior to this commit, only the letters 'A' - 'Z' (ignoring case) were
supported in identifiers (i.e., property, field, and variable names).
This known (yet undocumented) limitation prevented the use of characters
such as 'ü', 'ñ', 'é' as well as letters from other character sets such
as Chinese, Japanese, Cyrillic, etc.
This commit lifts that restriction by delegating to Character.isLetter()
to determine if a character in a SpEL expression is a letter.
Closes gh-30580
Prior to this commit, when an unsupported character such as "ü" was
encountered in a SpEL expression, the error message was:
Cannot handle (252) 'ü'
With this commit, the error message is now similar to:
Unsupported character 'ü' (252) encountered at position 5 in expression.
See gh-30580
Closes gh-30602
This commit adds support for MethodHandles in SpEL, using the same
syntax as user-defined functions (which also covers reflective Methods).
The most benefit is expected with handles that capture a static method
with no arguments, or with fully bound handles (where all the arguments
have been bound, including a target instance as first bound argument
if necessary). Partially bound MethodHandle should also be supported.
A best effort approach is taken to detect varargs as there is no API
support to determine if an argument is a vararg or an explicit array,
unlike with Method. Argument conversions are also applied. Finally,
array repacking is not always necessary with varargs so it is only
performed when the vararg is the sole argument to the invoked method.
See gh-27099
Closes gh-30045
This commit improves both the javadoc and the reference guide section on
the Elvis SpEL operator to clarify that in addition to `null` objects,
empty Strings also lead the operator to evaluate to its second operand.
The reference guide's advanced snippet is modified to use such an empty
String instead of `null` to make that behavior prominent with some code.
See gh-30318
Closes gh-30352
Prior to gh-30325, supplying a null reference for a SpEL expression was
effectively equivalent to supplying the String "null" as the
expression. Consequently, evaluation of a null reference expression
always evaluated to a null reference. However, that was accidental
rather than by design.
Due to the introduction of the checkExpressionLength(String) method in
InternalSpelExpressionParser (in conjunction with gh-30325), an attempt
to evaluate a null reference as a SpEL expression now results in a
NullPointerException.
To address both of these issues,
TemplateAwareExpressionParser.parseExpression() and
SpelExpressionParser.parseRaw() now reject null and empty SpEL
expressions.
Closes gh-30371
This commit introduces infrastructure to differentiate between
programmatic setting of a variable in an EvaluationContext versus the
assignment of a variable within a SpEL expression using the assignment
operator (=). In addition, this commit disables variable assignment
within expressions when using the SimpleEvaluationContext.
Closes gh-30326
This commit introduces support for limiting the maximum length of a
string resulting from the concatenation operator (+) in SpEL
expressions.
Closes gh-30324
This commit changes the max regex length in SpEL expressions from 1024
to 1000 in order to consistently use "round" numbers for recently
introduced limits.
See gh-30265
This commit increases the max regex length in SpEL expressions from 256
to 1024 in order to support use cases where a regex may be rather long
without necessarily increasing the complexity of the regex.
Closes gh-30265
This commit refactors some AssertJ assertions into more idiomatic and
readable ones. Using the dedicated assertion instead of a generic one
will produce more meaningful error messages.
For instance, consider collection size:
```
// expected: 5 but was: 2
assertThat(collection.size()).equals(5);
// Expected size: 5 but was: 2 in: [1, 2]
assertThat(collection).hasSize(5);
```
Closes gh-30104
Supplying a large regular expression to the `matches` operator in a
SpEL expression can result in errors that are not very helpful to the
user.
This commit improves the diagnostics in SpEL for the `matches` operator
by throwing a SpelEvaluationException with a meaningful error message
to better assist the user.
Closes gh-30144
Attempting to create repeated text in a SpEL expression using the
repeat operator can result in errors that are not very helpful to the
user.
This commit improves the diagnostics in SpEL for the repeat operator by
throwing a SpelEvaluationException with a meaningful error message in
order to better assist the user.
Closes gh-30142
Prior to this commit, the pattern cache for the SpEL `matches` operator
only applied to expressions such as the following where the same
`matches` operator is invoked multiple times with different input:
"map.keySet().?[#this matches '.+xyz']"
The pattern cache did not apply to expressions such as the following
where the same pattern ('.+xyz') is used in multiple `matches`
operations:
"foo matches '.+xyz' AND bar matches '.+xyz'"
This commit addresses this by moving the instance of the pattern cache
map from OperatorMatches to InternalSpelExpressionParser so that the
cache can be reused for all `matches` operations for the given parser.
Closes gh-30140