Package net.sourceforge.pmd.lang.java.rule.codestyle

Class UseDiamondOperatorRule

java.lang.Object

net.sourceforge.pmd.properties.AbstractPropertySource

net.sourceforge.pmd.lang.rule.AbstractRule

net.sourceforge.pmd.lang.java.rule.AbstractJavaRule

net.sourceforge.pmd.lang.java.rule.AbstractJavaRulechainRule

net.sourceforge.pmd.lang.java.rule.codestyle.UseDiamondOperatorRule

All Implemented Interfaces:

AstVisitor, JavaVisitor, Rule, PropertySource

public class UseDiamondOperatorRule
extends AbstractJavaRulechainRule

Checks usages of explicit type arguments in a constructor call that may be replaced by a diamond (<>). In order to determine this, we mock a type resolution call site, which is equivalent to the expression as if it had a diamond instead of explicit type arguments. We then perform overload resolution for this fake call site. If overload resolution fails, resolves to another overload, or if the inferred type is not compatible with the expected context type, then the type arguments are unnecessary, and removing them will not break the program.

Note that type inference in Java 8+ works differently from Java 7. In Java 7, type arguments may be necessary in more places. The specifics are however implemented within the type resolution code, and this rule does not need to know about it.

Field Summary

Fields inherited from interface net.sourceforge.pmd.lang.rule.Rule

VIOLATION_SUPPRESS_REGEX_DESCRIPTOR, VIOLATION_SUPPRESS_XPATH_DESCRIPTOR

Constructor Summary

Constructors

Constructor	Description
UseDiamondOperatorRule()

Method Summary

Modifier and Type	Method	Description
Object	visit(ASTConstructorCall ctorCall, Object data)

Methods inherited from class net.sourceforge.pmd.lang.java.rule.AbstractJavaRulechainRule

buildTargetSelector, visitJavaNode

Methods inherited from class net.sourceforge.pmd.lang.java.rule.AbstractJavaRule

apply, visitNode

Methods inherited from class net.sourceforge.pmd.lang.rule.AbstractRule

addExample, asCtx, deepCopy, dysfunctionReason, end, equals, getDescription, getExamples, getExternalInfoUrl, getLanguage, getMaximumLanguageVersion, getMessage, getMinimumLanguageVersion, getName, getPriority, getPropertySourceType, getRuleClass, getRuleSetName, getSince, getTargetSelector, hashCode, isDeprecated, setDeprecated, setDescription, setExternalInfoUrl, setLanguage, setMaximumLanguageVersion, setMessage, setMinimumLanguageVersion, setName, setPriority, setRuleClass, setRuleSetName, setSince, start

Methods inherited from class net.sourceforge.pmd.properties.AbstractPropertySource

definePropertyDescriptor, getOverriddenPropertiesByPropertyDescriptor, getOverriddenPropertyDescriptors, getPropertiesByPropertyDescriptor, getProperty, getPropertyDescriptor, getPropertyDescriptors, hasDescriptor, isPropertyOverridden, setProperty

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface net.sourceforge.pmd.lang.ast.AstVisitor

cannotVisit

Methods inherited from interface net.sourceforge.pmd.lang.java.ast.JavaVisitor

visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from interface net.sourceforge.pmd.properties.PropertySource

definePropertyDescriptor, getOverriddenPropertiesByPropertyDescriptor, getOverriddenPropertyDescriptors, getPropertiesByPropertyDescriptor, getProperty, getPropertyDescriptor, getPropertyDescriptors, hasDescriptor, isPropertyOverridden, setProperty

Methods inherited from interface net.sourceforge.pmd.lang.rule.Rule

initialize

Constructor Details

UseDiamondOperatorRule

public UseDiamondOperatorRule()

Method Details

visit

public Object visit(ASTConstructorCall ctorCall,
 Object data)