public class InnerAssignmentCheck extends AbstractCheck
Checks for assignments in subexpressions, such as in
String s = Integer.toString(i = 2);.
Rationale: With the exception of for iterators and assignment in while idiom,
all assignments should occur in their own top-level statement to increase readability.
With inner assignments like the one given above, it is difficult to see all places
where a variable is set.
Note: Check allows usage of the popular assignment in while idiom:
String line;
while ((line = bufferedReader.readLine()) != null) {
// process the line
}
Assignment inside a condition is not a problem here, as the assignment is surrounded
by an extra pair of parentheses. The comparison is != null and there is no chance that
intention was to write line == reader.readLine().
To configure the check:
<module name="InnerAssignment"/>
Example:
class MyClass {
void foo() {
int a, b;
a = b = 5; // violation, assignment to each variable should be in a separate statement
a = b += 5; // violation
a = 5; // OK
b = 5; // OK
a = 5; b = 5; // OK
double myDouble;
double[] doubleArray = new double[] {myDouble = 4.5, 15.5}; // violation
String nameOne;
List<String> myList = new ArrayList<String>();
myList.add(nameOne = "tom"); // violation
for (int k = 0; k < 10; k = k + 2) { // OK
// some code
}
boolean someVal;
if (someVal = true) { // violation
// some code
}
while (someVal = false) {} // violation
InputStream is = new FileInputStream("textFile.txt");
while ((b = is.read()) != -1) { // OK, this is a common idiom
// some code
}
}
boolean testMethod() {
boolean val;
return val = true; // violation
}
}
Parent is com.puppycrawl.tools.checkstyle.TreeWalker
Violation Message Keys:
assignment.inner.avoid
AutomaticBean.OutputStreamOptions| Modifier and Type | Field and Description |
|---|---|
static String |
MSG_KEY
A key is pointing to the warning message text in "messages.properties"
file.
|
| Constructor and Description |
|---|
InnerAssignmentCheck() |
| 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 |
visitToken(DetailAST ast)
Called to process a token.
|
beginTree, clearMessages, destroy, finishTree, getFileContents, getLine, getLines, getMessages, getTabWidth, getTokenNames, init, isCommentNodesRequired, leaveToken, log, log, log, setFileContents, setTabWidth, setTokensfinishLocalSetup, getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, setId, setSeverityconfigure, contextualize, getConfiguration, setupChildpublic static final String MSG_KEY
public InnerAssignmentCheck()
public int[] getDefaultTokens()
AbstractCheckgetDefaultTokens in class AbstractCheckTokenTypespublic int[] getAcceptableTokens()
AbstractCheckgetAcceptableTokens in class AbstractCheckTokenTypespublic int[] getRequiredTokens()
AbstractCheckgetRequiredTokens in class AbstractCheckTokenTypespublic void visitToken(DetailAST ast)
AbstractCheckvisitToken in class AbstractCheckast - the token to processCopyright © 2001–2020. All rights reserved.