Checkstyle 5.5

##### About

- Checkstyle
- Release Notes

##### Documentation

- Configuration
  - Property Types
- Running
  - Ant Task
  - Command Line
- Available Checks
- Standard Checks
  - Annotations
  - Block Checks
  - Class Design
  - Coding
  - Duplicate Code
  - Headers
  - Imports
  - Javadoc Comments
  - Metrics
  - Miscellaneous
  - Modifiers
  - Naming Conventions
  - Regexp
  - Size Violations
  - Whitespace
- Extending Checkstyle
  - Writing checks
  - Writing filters
  - Writing listeners

##### Developers

- Javadoc
- Project Page
- Contributing

##### Project Documentation

- Project Information
- Project Reports

## ExecutableStatementCount

### Description

Restricts the number of executable statements to a specified limit.

### Properties

name | description | type | default value
--- | --- | --- | ---
max | the maximum threshold allowed | integer | `30`
tokens | members to check | subset of tokens CTOR_DEF, METHOD_DEF, INSTANCE_INIT, STATIC_INIT | all tokens

### Examples

To configure the check:

    <module name="ExecutableStatementCount"/>

To configure the check with a threshold of 20 for constructor and method definitions:

    <module name="ExecutableStatementCount">
        <property name="max" value="20"/>
        <property name="tokens" value="CTOR_DEF,METHOD_DEF"/>
    </module>

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

TreeWalker

## FileLength

### Description

Checks for long source files.

Rationale: If a source file becomes very long it is hard to understand. Therefore long classes should usually be refactored into several individual classes that focus on a specific task.

### Properties

name | description | type | default value
--- | --- | --- | ---
max | maximum allowable number of lines | integer | 2000
fileExtensions | file type extension of files to process | String Set | `{}`

### Examples

To configure the check to accept files with up to 1500 lines:

    <module name="FileLength">
          <property name="max" value="1500"/>
    </module>

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

Checker

## LineLength

### Description

Checks for long lines.

Rationale: Long lines are hard to read in printouts or if developers have limited screen space for the source code, e.g. if the IDE displays additional information like project tree, class hierarchy, etc.

### Properties

name | description | type | default value
--- | --- | --- | ---
ignorePattern | pattern for lines to ignore | regular expression | ^$
max | maximum allowable line length | integer | 80

### Examples

To configure the check to accept lines up to 120 characters long:

    <module name="LineLength">
        <property name="max" value="120"/>
    </module>

To configure the check to ignore lines that begin with " * ", followed by just one word, such as within a Javadoc comment:

    <module name="LineLength">
       <property name="ignorePattern" value="^ *\* *[^ ]+$"/>
    </module>

### Notes

- The calculation of the length of a line takes into account the number of expanded spaces for a tab character (`'\t'`). The default number of spaces is `8`. To specify a different number of spaces, the user can set `TreeWalker` property `tabWidth` which applies to all Checks, including `LineLength`; or can set property `tabWidth` for `LineLength` alone.
- Support for the special handling of imports in CheckStyle Version 2 has been dropped as it is a special case of regexp: The user can set property `ignorePattern` to `^import` and achieve the same effect.

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

TreeWalker

## MethodLength

### Description

Checks for long methods and constructors.

Rationale: If a method becomes very long it is hard to understand. Therefore long methods should usually be refactored into several individual methods that focus on a specific task.

### Properties

name | description | type | default value
--- | --- | --- | ---
max | maximum allowable number of lines | integer | 150
countEmpty | whether to count empty lines and single line comments of the form `//` | boolean | `true`
tokens | blocks to check | subset of tokens METHOD_DEF, CTOR_DEF | METHOD_DEF, CTOR_DEF

### Examples

To configure the check:

    <module name="MethodLength"/>

To configure the check so that it accepts methods with at most 60 lines:

    <module name="MethodLength">
       <property name="tokens" value="METHOD_DEF"/>
       <property name="max" value="60"/>
    </module>

To configure the check so that it accepts methods with at most 60 lines, not counting empty lines and single line comments:

    <module name="MethodLength">
       <property name="tokens" value="METHOD_DEF"/>
       <property name="max" value="60"/>
       <property name="countEmpty" value="false"/>
    </module>

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

TreeWalker

## AnonInnerLength

### Description

Checks for long anonymous inner classes.

Rationale: If an anonymous inner class becomes very long it is hard to understand and to see the flow of the method where the class is defined. Therefore long anonymous inner classes should usually be refactored into a named inner class. See also Bloch, Effective Java, p. 93.

### Properties

name | description | type | default value
--- | --- | --- | ---
max | maximum allowable number of lines | integer | 20

### Examples

To configure the check to accept files with up to 60 lines:

    <module name="AnonInnerLength">
          <property name="max" value="60"/>
    </module>

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

TreeWalker

## ParameterNumber

### Description

Checks the number of parameters of a method or constructor.

### Properties

name | description | type | default value
--- | --- | --- | ---
max | maximum allowable number of parameters | integer | 7
tokens | declarations to check | subset of tokens METHOD_DEF, CTOR_DEF | METHOD_DEF, CTOR_DEF

### Examples

To configure the check:

    <module name="ParameterNumber"/>

To configure the check to allow 10 parameters for a method:

    <module name="ParameterNumber">
       <property name="max" value="10"/>
       <property name="tokens" value="METHOD_DEF"/>
    </module>

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

TreeWalker

## OuterTypeNumber

### Description

Checks for the number of types declared at the outer (or root) level in a file.

Rationale: It is considered good practice to only define one outer type per file.

### Properties

name | description | type | default value
--- | --- | --- | ---
max | maximum allowable number of outer types | integer | 1

### Examples

To configure the check to accept 1 outer type per file:

    <module name="OuterTypeNumber"/>

To configure the check to accept 2 outer types per file:

    <module name="OuterTypeNumber">
          <property name="max" value="2"/>
    </module>

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

TreeWalker

## MethodCount

### Description

Checks the number of methods declared in each type. This includes the number of each scope (`private`, `package`, `protected` and `public`) as well as an overall total.

### Properties

name | description | type | default value
--- | --- | --- | ---
maxTotal | maximum allowable number of methods at all scope levels | integer | 100
maxPrivate | maximum allowable number of `private` methods | integer | 100
maxPackage | maximum allowable number of `package` methods | integer | 100
maxProtected | maximum allowable number of `protected` methods | integer | 100
maxPublic | maximum allowable number of `public` methods | integer | 100

### Examples

To configure the check with defaults:

    <module name="MethodCount"/>

To configure the check to allow at most 30 methods per type:

    <module name="MethodCount">
          <property name="maxTotal" value="30"/>
    </module>

### Package

com.puppycrawl.tools.checkstyle.checks.sizes

### Parent Module

TreeWalker