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Java Exceptions & Errors

Java 2123 codes

java.lang, java.io, java.net, java.sql and concurrent exceptions

Showing 23 of 23 errors

Code	Message	Severity	Tier
NullPointerException	Null reference accessed	FATAL	Common	→
ArrayIndexOutOfBoundsException	Array index out of bounds	FATAL	Common	→
ClassCastException	Invalid class cast	FATAL	Common	→
NumberFormatException	Invalid number format string	ERROR	Common	→
IllegalArgumentException	Illegal or inappropriate method argument	ERROR	Common	→
IllegalStateException	Object in illegal state for this operation	ERROR	Notable	→
StackOverflowError	Call stack depth exceeded	FATAL	Notable	→
OutOfMemoryError	JVM heap space exhausted	FATAL	Critical	→
FileNotFoundException	File does not exist or cannot be opened	ERROR	Common	→
IOException	I/O operation failed	ERROR	Common	→
SocketException	Socket operation failed — connection broken or refused	ERROR	Notable	→
UnknownHostException	DNS resolution failed for hostname	ERROR	Notable	→
ClassNotFoundException	Class not found on classpath	FATAL	Notable	→
SQLException	Database access error	ERROR	Notable	→
InterruptedException	Thread interrupted while blocked	WARNING	Notable	→
ConcurrentModificationException	Collection modified during iteration	ERROR	Common	→
ArithmeticException	Arithmetic error — usually division by zero	ERROR	Common	→
UnsupportedOperationException	Operation not supported on this collection	ERROR	Common	→
NoSuchElementException	No element available in iterator or Optional	ERROR	Common	→
TimeoutException	Operation timed out before completing	ERROR	Notable	→
ExecutionException	Exception thrown by async task (wrapped)	ERROR	Notable	→
ClassFormatError	Class file format is invalid	FATAL	Critical	→
AssertionError	Assertion failed — internal invariant violated	FATAL	Notable	→