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Walkmod plugin to automatically fix the reported problems by PMD
<?xml version="1.0"?>
<ruleset name="Strict Exceptions"
xmlns="http://pmd.sourceforge.net/ruleset/2.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://pmd.sourceforge.net/ruleset/2.0.0 http://pmd.sourceforge.net/ruleset_2_0_0.xsd">
<description>
These rules provide some strict guidelines about throwing and catching exceptions.
</description>
<rule name="AvoidCatchingThrowable"
since="1.2"
message="A catch statement should never catch throwable since it includes errors."
class="net.sourceforge.pmd.lang.java.rule.strictexception.AvoidCatchingThrowableRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidCatchingThrowable">
<description>
Catching Throwable errors is not recommended since its scope is very broad. It includes runtime issues such as
OutOfMemoryError that should be exposed and managed separately.
</description>
<priority>3</priority>
<example>
<![CDATA[
public void bar() {
try {
// do something
} catch (Throwable th) { // should not catch Throwable
th.printStackTrace();
}
}
]]>
</example>
</rule>
<rule name="SignatureDeclareThrowsException"
since="1.2"
message="A method/constructor shouldn't explicitly throw java.lang.Exception"
class="net.sourceforge.pmd.lang.java.rule.strictexception.SignatureDeclareThrowsExceptionRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#SignatureDeclareThrowsException">
<description>
Methods that declare the generic Exception as a possible throwable are not very helpful since their
failure modes are unclear. Use a class derived from RuntimeException or a more specific checked exception.
</description>
<priority>3</priority>
<example>
<![CDATA[
public void foo() throws Exception {
}
]]>
</example>
</rule>
<rule name="ExceptionAsFlowControl"
since="1.8"
message="Avoid using exceptions as flow control."
class="net.sourceforge.pmd.lang.java.rule.strictexception.ExceptionAsFlowControlRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#ExceptionAsFlowControl">
<description>
Using Exceptions as form of flow control is not recommended as they obscure true exceptions when debugging.
Either add the necessary validation or use an alternate control structure.
</description>
<priority>3</priority>
<example>
<![CDATA[
public void bar() {
try {
try {
} catch (Exception e) {
throw new WrapperException(e);
// this is essentially a GOTO to the WrapperException catch block
}
} catch (WrapperException e) {
// do some more stuff
}
}
]]>
</example>
</rule>
<rule name="AvoidCatchingNPE"
language="java"
since="1.8"
message="Avoid catching NullPointerException; consider removing the cause of the NPE."
class="net.sourceforge.pmd.lang.rule.XPathRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidCatchingNPE">
<description>
Code should never throw NullPointerExceptions under normal circumstances. A catch block may hide the
original error, causing other, more subtle problems later on.
</description>
<priority>3</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//CatchStatement/FormalParameter/Type
/ReferenceType/ClassOrInterfaceType[@Image='NullPointerException']
]]>
</value>
</property>
</properties>
<example> <![CDATA[
public class Foo {
void bar() {
try {
// do something
} catch (NullPointerException npe) {
}
}
}
]]>
</example>
</rule>
<rule name="AvoidThrowingRawExceptionTypes"
language="java"
since="1.8"
message="Avoid throwing raw exception types."
class="net.sourceforge.pmd.lang.rule.XPathRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidThrowingRawExceptionTypes">
<description>
Avoid throwing certain exception types. Rather than throw a raw RuntimeException, Throwable,
Exception, or Error, use a subclassed exception or error instead.
</description>
<priority>1</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//ThrowStatement//AllocationExpression
/ClassOrInterfaceType[
(@Image='Throwable' and count(//ImportDeclaration/Name[ends-with(@Image,'Throwable')]) = 0)
or
(@Image='Exception' and count(//ImportDeclaration/Name[ends-with(@Image,'Exception')]) = 0)
or
(@Image='Error' and count(//ImportDeclaration/Name[ends-with(@Image,'Error')]) = 0)
or
( @Image='RuntimeException' and count(//ImportDeclaration/Name[ends-with(@Image,'RuntimeException')]) = 0)
]
]]>
</value>
</property>
</properties>
<example>
<![CDATA[
public class Foo {
public void bar() throws Exception {
throw new Exception();
}
}
]]>
</example>
</rule>
<rule name="AvoidThrowingNullPointerException"
language="java"
since="1.8"
message="Avoid throwing null pointer exceptions."
class="net.sourceforge.pmd.lang.rule.XPathRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidThrowingNullPointerException">
<description>
Avoid throwing NullPointerExceptions. These are confusing because most people will assume that the
virtual machine threw it. Consider using an IllegalArgumentException instead; this will be
clearly seen as a programmer-initiated exception.
</description>
<priority>1</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//AllocationExpression/ClassOrInterfaceType[@Image='NullPointerException']
]]>
</value>
</property>
</properties>
<example>
<![CDATA[
public class Foo {
void bar() {
throw new NullPointerException();
}
}
]]>
</example>
</rule>
<rule name="AvoidRethrowingException"
language="java"
since="3.8"
message="A catch statement that catches an exception only to rethrow it should be avoided."
class="net.sourceforge.pmd.lang.rule.XPathRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidRethrowingException">
<description>
Catch blocks that merely rethrow a caught exception only add to code size and runtime complexity.
</description>
<priority>3</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//CatchStatement[FormalParameter
/VariableDeclaratorId/@Image = Block/BlockStatement/Statement
/ThrowStatement/Expression/PrimaryExpression[count(PrimarySuffix)=0]/PrimaryPrefix/Name/@Image
and count(Block/BlockStatement/Statement) =1]
]]>
</value>
</property>
</properties>
<example> <![CDATA[
public void bar() {
try {
// do something
} catch (SomeException se) {
throw se;
}
}
]]>
</example>
</rule>
<rule
name="DoNotExtendJavaLangError"
language="java"
since="4.0"
message="Exceptions should not extend java.lang.Error"
class="net.sourceforge.pmd.lang.rule.XPathRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#DoNotExtendJavaLangError">
<description>
<![CDATA[
Errors are system exceptions. Do not extend them.
]]>
</description>
<priority>3</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//ClassOrInterfaceDeclaration/ExtendsList/ClassOrInterfaceType
[@Image="Error" or @Image="java.lang.Error"]
]]>
</value>
</property>
</properties>
<example><![CDATA[
public class Foo extends Error { }
]]></example>
</rule>
<rule name="DoNotThrowExceptionInFinally"
language="java"
since="4.2"
message="A throw statement in a finally block makes the control flow hard to understand."
class="net.sourceforge.pmd.lang.rule.XPathRule"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#DoNotThrowExceptionInFinally">
<description>
<![CDATA[
Throwing exceptions within a 'finally' block is confusing since they may mask other exceptions
or code defects.
Note: This is a PMD implementation of the Lint4j rule "A throw in a finally block"
]]>
</description>
<priority>4</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//FinallyStatement[descendant::ThrowStatement]
]]>
</value>
</property>
</properties>
<example>
<![CDATA[
public class Foo {
public void bar() {
try {
// Here do some stuff
} catch( Exception e) {
// Handling the issue
} finally {
// is this really a good idea ?
throw new Exception();
}
}
}
]]>
</example>
</rule>
<rule name="AvoidThrowingNewInstanceOfSameException"
since="4.2.5" language="java"
message="A catch statement that catches an exception only to wrap it in a new instance of the same type of exception and throw it should be avoided"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidThrowingNewInstanceOfSameException"
class="net.sourceforge.pmd.lang.rule.XPathRule">
<description>
Catch blocks that merely rethrow a caught exception wrapped inside a new instance of the same type only add to
code size and runtime complexity.
</description>
<priority>3</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//CatchStatement[
count(Block/BlockStatement/Statement) = 1
and
FormalParameter/Type/ReferenceType/ClassOrInterfaceType/@Image = Block/BlockStatement/Statement/ThrowStatement/Expression/PrimaryExpression/PrimaryPrefix/AllocationExpression/ClassOrInterfaceType/@Image
and
count(Block/BlockStatement/Statement/ThrowStatement/Expression/PrimaryExpression/PrimaryPrefix/AllocationExpression/Arguments/ArgumentList/Expression) = 1
and
FormalParameter/VariableDeclaratorId = Block/BlockStatement/Statement/ThrowStatement/Expression/PrimaryExpression/PrimaryPrefix/AllocationExpression/Arguments/ArgumentList/Expression/PrimaryExpression/PrimaryPrefix/Name
]
]]>
</value>
</property>
</properties>
<example> <![CDATA[
public void bar() {
try {
// do something
} catch (SomeException se) {
// harmless comment
throw new SomeException(se);
}
}
]]>
</example>
</rule>
<rule name="AvoidCatchingGenericException"
since="4.2.6" language="java"
message="Avoid catching generic exceptions such as NullPointerException, RuntimeException, Exception in try-catch block"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidCatchingGenericException"
class="net.sourceforge.pmd.lang.rule.XPathRule">
<description>
Avoid catching generic exceptions such as NullPointerException, RuntimeException, Exception in try-catch block
</description>
<priority>3</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//CatchStatement/FormalParameter/Type/ReferenceType/ClassOrInterfaceType[
@Image='NullPointerException' or
@Image='Exception' or
@Image='RuntimeException']
]]>
</value>
</property>
</properties>
<example>
<![CDATA[
package com.igate.primitive;
public class PrimitiveType {
public void downCastPrimitiveType() {
try {
System.out.println(" i [" + i + "]");
} catch(Exception e) {
e.printStackTrace();
} catch(RuntimeException e) {
e.printStackTrace();
} catch(NullPointerException e) {
e.printStackTrace();
}
}
}
]]>
</example>
</rule>
<rule name="AvoidLosingExceptionInformation"
since="4.2.6" language="java"
message="Avoid statements in a catch block that invoke accessors on the exception without using the information"
externalInfoUrl="https://pmd.github.io/pmd-5.4.1/pmd-java/rules/java/strictexception.html#AvoidLosingExceptionInformation"
class="net.sourceforge.pmd.lang.rule.XPathRule">
<description>
Statements in a catch block that invoke accessors on the exception without using the information
only add to code size. Either remove the invocation, or use the return result.
</description>
<priority>2</priority>
<properties>
<property name="xpath">
<value>
<![CDATA[
//CatchStatement/Block/BlockStatement/Statement/StatementExpression/PrimaryExpression/PrimaryPrefix/Name
[
@Image = concat(../../../../../../../FormalParameter/VariableDeclaratorId/@Image, '.getMessage')
or
@Image = concat(../../../../../../../FormalParameter/VariableDeclaratorId/@Image, '.getLocalizedMessage')
or
@Image = concat(../../../../../../../FormalParameter/VariableDeclaratorId/@Image, '.getCause')
or
@Image = concat(../../../../../../../FormalParameter/VariableDeclaratorId/@Image, '.getStackTrace')
or
@Image = concat(../../../../../../../FormalParameter/VariableDeclaratorId/@Image, '.toString')
]
]]>
</value>
</property>
</properties>
<example>
<![CDATA[
public void bar() {
try {
// do something
} catch (SomeException se) {
se.getMessage();
}
}
]]>
</example>
</rule>
</ruleset> © 2015 - 2025 Weber Informatics LLC | Privacy Policy