UnnecessaryParenthesesCheck (checkstyle 8.8 API)

java.lang.Object
- com.puppycrawl.tools.checkstyle.api.AutomaticBean
- - com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
  - - com.puppycrawl.tools.checkstyle.api.AbstractCheck
    - - com.puppycrawl.tools.checkstyle.checks.coding.UnnecessaryParenthesesCheck

All Implemented Interfaces:

Configurable, Contextualizable
```
public class UnnecessaryParenthesesCheck
extends AbstractCheck
```
Checks if unnecessary parentheses are used in a statement or expression. The check will flag the following with warnings:
```
     return (x);          // parens around identifier
     return (x + 1);      // parens around return value
     int x = (y / 2 + 1); // parens around assignment rhs
     for (int i = (0); i < 10; i++) {  // parens around literal
     t -= (z + 1);        // parens around assignment rhs
```
The check is not "type aware", that is to say, it can't tell if parentheses are unnecessary based on the types in an expression. It also doesn't know about operator precedence and associativity; therefore it won't catch something like
```
     int x = (a + b) + c;
```
In the above case, given that a, b, and c are all int variables, the parentheses around a + b are not needed.
Author:

Eric Roe

Nested Class Summary
- Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean
  AutomaticBean.OutputStreamOptions

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`MSG_ASSIGN` A key is pointing to the warning message text in "messages.properties" file.
`static String`	`MSG_EXPR` A key is pointing to the warning message text in "messages.properties" file.
`static String`	`MSG_IDENT` A key is pointing to the warning message text in "messages.properties" file.
`static String`	`MSG_LAMBDA` A key is pointing to the warning message text in "messages.properties" file.
`static String`	`MSG_LITERAL` A key is pointing to the warning message text in "messages.properties" file.
`static String`	`MSG_RETURN` A key is pointing to the warning message text in "messages.properties" file.
`static String`	`MSG_STRING` A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors
Constructor and Description

UnnecessaryParenthesesCheck()

Constructors
Constructor and Description
`UnnecessaryParenthesesCheck()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int[]`	`getAcceptableTokens()` The configurable token set.
`int[]`	`getDefaultTokens()` Returns the default token a check is interested in.
`int[]`	`getRequiredTokens()` The tokens that this check must be registered for.
`void`	`leaveToken(DetailAST ast)` Called after all the child nodes have been process.
`void`	`visitToken(DetailAST ast)` Called to process a token.

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck
beginTree, clearMessages, destroy, finishTree, getClassLoader, getFileContents, getLine, getLines, getMessages, getTabWidth, getTokenNames, init, isCommentNodesRequired, log, log, log, setClassLoader, setFileContents, setTabWidth, setTokens

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
finishLocalSetup, getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, setId, setSeverity

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean
configure, contextualize, getConfiguration, setupChild

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - MSG_IDENT
```
public static final String MSG_IDENT
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_ASSIGN
```
public static final String MSG_ASSIGN
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_EXPR
```
public static final String MSG_EXPR
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_LITERAL
```
public static final String MSG_LITERAL
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_STRING
```
public static final String MSG_STRING
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_RETURN
```
public static final String MSG_RETURN
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
  - MSG_LAMBDA
```
public static final String MSG_LAMBDA
```
    A key is pointing to the warning message text in "messages.properties" file.
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - UnnecessaryParenthesesCheck
```
public UnnecessaryParenthesesCheck()
```
- Method Detail
  - getDefaultTokens
```
public int[] getDefaultTokens()
```
    Description copied from class: AbstractCheck
    
    Returns the default token a check is interested in. Only used if the configuration for a check does not define the tokens.
    
    Specified by:
    
    getDefaultTokens in class AbstractCheck
    
    Returns:
    
    the default tokens
    
    See Also:
    
    TokenTypes
  - getAcceptableTokens
```
public int[] getAcceptableTokens()
```
    Description copied from class: AbstractCheck
    
    The configurable token set. Used to protect Checks against malicious users who specify an unacceptable token set in the configuration file. The default implementation returns the check's default tokens.
    
    Specified by:
    
    getAcceptableTokens in class AbstractCheck
    
    Returns:
    
    the token set this check is designed for.
    
    See Also:
    
    TokenTypes
  - getRequiredTokens
```
public int[] getRequiredTokens()
```
    Description copied from class: AbstractCheck
    
    The tokens that this check must be registered for.
    
    Specified by:
    
    getRequiredTokens in class AbstractCheck
    
    Returns:
    
    the token set this must be registered for.
    
    See Also:
    
    TokenTypes
  - visitToken
```
public void visitToken(DetailAST ast)
```
    Description copied from class: AbstractCheck
    
    Called to process a token.
    
    Overrides:
    
    visitToken in class AbstractCheck
    
    Parameters:
    
    ast - the token to process
  - leaveToken
```
public void leaveToken(DetailAST ast)
```
    Description copied from class: AbstractCheck
    
    Called after all the child nodes have been process.
    
    Overrides:
    
    leaveToken in class AbstractCheck
    
    Parameters:
    
    ast - the token leaving

Class UnnecessaryParenthesesCheck

Nested Class Summary

Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

Field Summary

Constructor Summary

Method Summary

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

Methods inherited from class java.lang.Object

Field Detail

MSG_IDENT

MSG_ASSIGN

MSG_EXPR

MSG_LITERAL

MSG_STRING

MSG_RETURN

MSG_LAMBDA

Constructor Detail

UnnecessaryParenthesesCheck

Method Detail

getDefaultTokens

getAcceptableTokens

getRequiredTokens

visitToken

leaveToken