Performance

'Collection.toArray()' call style: Reports Collection.toArray() calls that are not in the preferred style, and suggests applying the preferred style.
'InputStream' and 'OutputStream' can be constructed using 'Files' methods: Reports new FileInputStream() or new FileOutputStream() expressions that can be replaced with Files.newInputStream() or Files.newOutputStream() calls respectively.
'List.remove()' called in loop: Reports List.remove(index) called in a loop that can be replaced with List.subList().clear().
'Map' can be replaced with 'EnumMap': Reports instantiations of java.util.Map objects whose key types are enumerated classes.
'Set' can be replaced with 'EnumSet': Reports instantiations of java.util.Set objects whose content types are enumerated classes.
'String.equals()' can be replaced with 'String.isEmpty()': Reports equals() being called to compare a String with an empty string.
'StringBuilder' without initial capacity: Reports attempts to instantiate a new StringBuffer or StringBuilder object without specifying its initial capacity.
'StringBuilder.toString()' in concatenation: Reports StringBuffer.toString() or StringBuilder.toString() calls in string concatenations.
'equals()' call can be replaced with '==': Reports calls to equals() that can be replaced by == or != expressions without a change in semantics.
Auto-boxing: Reports expressions that are affected by autoboxing conversion (automatic wrapping of primitive values as objects).
Auto-unboxing: Reports expressions that are affected by unboxing conversion (automatic unwrapping of objects into primitive values).
Boolean constructor call: Reports creation of Boolean objects.
Boxing of already boxed value: Reports boxing of already boxed values.
Bulk 'Files.readAttributes()' call can be used: Reports multiple sequential java.io.File attribute checks, such as: isDirectory() isFile() lastModified() length() Such calls can be replaced with a bulk Files.readAttributes() call.
Bulk operation can be used instead of iteration: Reports single operations inside loops that could be replaced with a bulk method.
Call to 'Arrays.asList()' with too few arguments: Reports calls to Arrays.asList() with at most one argument.
Call to 'list.containsAll(collection)' may have poor performance: Reports calls to containsAll() on java.util.List.
Call to 'set.removeAll(list)' may work slowly: Reports calls to java.util.Set.removeAll() with a java.util.List argument.
Call to simple getter from within class: Reports calls to a simple property getter from within the property's class.
Call to simple setter from within class: Reports calls to a simple property setter from within the property's class.
Class initializer may be 'static': Reports instance initializers which may be made static.
Collection without initial capacity: Reports attempts to instantiate a new Collection object without specifying an initial capacity.
Dynamic regular expression could be replaced by compiled 'Pattern': Reports calls to the regular expression methods (such as matches() or split()) of java.lang.String using constant arguments.
Early loop exit in 'if' condition: Reports loops with an if statement that can end with break without changing the semantics.
Explicit argument can be lambda: Reports method calls that accept a non-trivial expression and can be replaced with an equivalent method call which accepts a lambda instead.
Field can be made 'static': Reports instance variables that can safely be made static.
Inefficient Stream API call chains ending with count(): Reports Stream API call chains ending with the count() operation that could be optimized.
Instantiating object to get 'Class' object: Reports code that instantiates a class to get its class object.
Iteration over 'keySet()' can be optimized: Reports iterations over the keySet() of a java.util.Map instance, where the iterated keys are used to retrieve the values from the map.
Manual array copy: Reports manual copying of array contents that can be replaced with a call to System.arraycopy().
Manual array to collection copy: Reports code that uses a loop to copy the contents of an array into a collection.
Method can be made 'static': Reports methods that can safely be made static.
Non-constant 'String' can be replaced with 'StringBuilder': Reports variables declared as java.lang.String that are repeatedly appended to.
Object allocation in loop: Reports object or array allocations inside loops.
Object instantiation inside 'equals()' or 'hashCode()': Reports construction of (temporary) new objects inside equals(), hashCode(), compareTo(), and Comparator.compare() methods.
Redundant 'Collection.addAll()' call: Reports Collection.addAll() and Map.putAll() calls immediately after an instantiation of a collection using a no-arg constructor.
Redundant call to 'String.format()': Reports calls to methods like format() and printf() that can be safely removed or simplified.
Single character string argument in 'String.indexOf()' call: Reports single character strings being used as an argument in String.indexOf() and String.lastIndexOf() calls.
Single character string concatenation: Reports concatenation with string literals that consist of one character.
String concatenation as argument to 'StringBuilder.append()' call: Reports String concatenation used as the argument to StringBuffer.append(), StringBuilder.append() or Appendable.append().
String concatenation in loop: Reports String concatenation in loops.
Tail recursion: Reports tail recursion, that is, when a method calls itself as its last action before returning.
Unnecessary temporary object in conversion from 'String': Reports unnecessary creation of temporary objects when converting from String to primitive types.
Unnecessary temporary object in conversion to 'String': Reports unnecessary creation of temporary objects when converting from a primitive type to String.
Using 'Random.nextDouble()' to get random integer: Reports calls to java.util.Random.nextDouble() that are used to create a positive integer number by multiplying the call by a factor and casting to an integer.
Wrapper type may be primitive: Reports local variables of wrapper type that are mostly used as primitive types.
Embedded: Sub-group of 11 inspections that provide checks for Embedded

Last modified: 18 June 2024