net.sourceforge.pmd.lang.java.ast.ASTLambdaExpression Maven / Gradle / Ivy
/**
* BSD-style license; for more info see http://pmd.sourceforge.net/license.html
*/
package net.sourceforge.pmd.lang.java.ast;
import org.checkerframework.checker.nullness.qual.NonNull;
import org.checkerframework.checker.nullness.qual.Nullable;
import net.sourceforge.pmd.lang.java.types.JMethodSig;
import net.sourceforge.pmd.lang.java.types.JTypeMirror;
/**
* A lambda expression.
*
*
*
*
* LambdaExpression ::= {@link ASTLambdaParameterList LambdaParameterList} {@code "->"} ( {@link ASTExpression Expression} | {@link ASTBlock Block} )
*
*
*/
public final class ASTLambdaExpression extends AbstractJavaExpr implements FunctionalExpression {
private JMethodSig functionalMethod;
ASTLambdaExpression(int id) {
super(id);
}
/**
* Returns the type of the functional interface.
* E.g. in {@code stringStream.map(s -> s.isEmpty())}, this is
* {@code java.util.function.Function}.
*
* @see #getFunctionalMethod()
*/
@Override
public @NonNull JTypeMirror getTypeMirror() {
return super.getTypeMirror();
}
/**
* Returns the method that is overridden in the functional interface.
* E.g. in {@code stringStream.map(s -> s.isEmpty())}, this is
* {@code java.util.function.Function#apply(java.lang.String) ->
* java.lang.Boolean}
*
* @see #getTypeMirror()
*/
@Override
public JMethodSig getFunctionalMethod() {
forceTypeResolution();
return assertNonNullAfterTypeRes(functionalMethod);
}
void setFunctionalMethod(@Nullable JMethodSig functionalMethod) {
this.functionalMethod = functionalMethod;
}
public ASTLambdaParameterList getParameters() {
return (ASTLambdaParameterList) getChild(0);
}
/**
* Return true if this lambda is explicitly typed, meaning
* all parameters have an explicit type. Note that lambdas
* with zero parameters are explicitly typed.
*/
public boolean isExplicitlyTyped() {
return getParameters().toStream().none(ASTLambdaParameter::isTypeInferred);
}
/** Returns true if this lambda has a block for body. */
public boolean isBlockBody() {
return getChild(1) instanceof ASTBlock;
}
/** Returns true if this lambda has an expression for body. */
public boolean isExpressionBody() {
return !isBlockBody();
}
/**
* Returns the body of this expression, if it is a block.
*
* @deprecated Use {@link #getBlockBody()}
*/
@Deprecated
public @Nullable ASTBlock getBlock() {
return getBlockBody();
}
/**
* Returns the body of this expression, if it is an expression.
*
* @deprecated Use {@link #getExpressionBody()}
*/
@Deprecated
public @Nullable ASTExpression getExpression() {
return getExpressionBody();
}
/**
* Returns the body of this lambda if it is a block.
*/
public @Nullable ASTBlock getBlockBody() {
return AstImplUtil.getChildAs(this, 1, ASTBlock.class);
}
/**
* Returns the body of this lambda if it is an expression.
*/
public @Nullable ASTExpression getExpressionBody() {
return AstImplUtil.getChildAs(this, 1, ASTExpression.class);
}
@Override
public boolean isFindBoundary() {
return true;
}
/**
* Returns the number of formal parameters of this lambda.
*/
public int getArity() {
return getParameters().size();
}
@Override
protected R acceptVisitor(JavaVisitor visitor, P data) {
return visitor.visit(this, data);
}
}