Mob SMS authentication userinterruptexception is how to return a responsibility?

You must encounter this exception often. The explanation of the exception is "the program encountered a null pointer", which is simply to call an uninitialized object or a nonexistent object. This error often occurs in the operations of creating images and calling arrays, such as the image is not initialized or the path is wrong when creating images. In many cases, the null pointer in array operation is a common mistake made by some friends who are just beginning to learn programming, that is, the initialization of array is confused with the initialization of array elements. The initialization of the array is to allocate the required space for the array, and the elements in the initialized array are still empty without instantiation, so each element needs to be initialized (if it is to be called).

2.Java . lang . classnotfoundexception

This exception is a common problem for many programmers who originally developed in jb and other development environments to compile packages under jb under wtk. The exception is interpreted as "the specified class does not exist". The main consideration here is whether the name and path of the class are correct. If it is a package made under jb, the package is usually added by default, so pay attention to the path of adding the package after switching to wtk.

3.java.lang.arithmeticexception

The explanation for this anomaly is "abnormal mathematical operation". For example, if there is an operation such as dividing by zero in the program, such an exception will appear. For this kind of abnormality, everyone should carefully check the places involved in mathematical operations in their own programs and whether the formulas are inappropriate.

4.Java . lang . arrayindexoutofboundsexception

I believe many friends often encounter this exception. The explanation of the exception is "array subscript out of bounds". Most programs now operate on arrays, so when calling arrays, we must carefully check to see if the subscripts we call are beyond the range of arrays. Generally speaking, it is not easy to make such mistakes in display (that is, directly using constants as subscripts) calls, while implicit (that is, using variables as subscripts) calls often make mistakes. There is another situation. But the length of the array defined in the program is determined by some specific methods, not declared in advance. At this point, it is best to check the length of the array first to avoid this exception.

5.Java . lang . illegalargumentexception

The explanation of this exception is "parameter error of method". Many methods in j2me class library will lead to such errors in some cases. For example, if the volume parameter in the volume adjustment method is written as a negative number, this exception will occur. For example, if there are more than 255 values in the method of G. SetColor (int red, int green, int blue), this exception will also appear. So once this anomaly is found, what we need to do is to quickly check the method.

6.Java . lang . illegalaccessexception

The explanation of this exception is "no access rights". This exception occurs when an application wants to call a class, but the current method does not have permission to access the class. Note this exception when using a package in a program.

There are many other anomalies, so I won't list them one by one. What I want to explain is that a qualified programmer needs to have a good understanding of the common problems in the program and the corresponding solutions, otherwise, if he just stays in writing the program without making changes, it will greatly affect his own development. Descriptions of all exceptions can be found in the api.

Arithmetic exception class: arithmetic exception

Nullpointerexception class: NullPointerException

Type conversion exception: ClassCastException

Array negative subscript exception: NegativeArrayException

Array subscript out-of-bounds exception: ArrayIndexOutOfBoundsException

Exception that violates security principle: SecturityException

End of file exception: EOFException

No exception found in the file: FileNotFoundException.

String conversion to number exception: NumberFormatException

Operation database exception: SQLException

Input/output exception: IOException

No exception was found in this method: NoSuchMethodException.

java.lang.AbstractMethodError

Errors in abstract methods. Thrown when an application attempts to call an abstract method.

java.lang.AssertionError

The assertion is wrong. Used to indicate the failure of assertion.

Java . lang . class circularity error

Class circular dependency error. When initializing classes, this exception will be thrown if circular dependencies between classes are detected.

java.lang.ClassFormatError

The category format is wrong. Thrown when a Java virtual machine tries to read a Java class from a file and detects that the contents of the file do not conform to the valid format of the class.

Java.lang error

Mistake. Is the base class for all errors and is used to identify serious program running problems. These problems usually describe some exceptions that should not be caught by the application.

Java . lang . exceptioniniinitializererror

Initialization program error. Thrown when an exception occurs during the execution of a static initializer of a class. A static initializer refers to a static statement segment directly contained in a class.

java.lang.IllegalAccessError

Illegal access error. This exception is thrown when an application attempts to access, modify a field of a class or call its method, but it violates the visibility declaration of the field or method.

Java . lang . incompatilleclasschangeerror

Incompatible class change error. This exception is thrown when an incompatible change occurs to the class definition on which the execution method depends. Generally speaking, it is easy to cause this error by modifying the declaration definitions of some classes in the application without recompiling the whole application and running it directly.

java.lang.InstantiationError

Instantiation error. This exception is thrown when an application tries to construct an abstract class or interface through a new operator in Java.

java.lang.InternalError

Internal error. Used to indicate that an internal error has occurred in the Java virtual machine.

java.lang.LinkageError

Link error. This error and all its subclasses indicate that one class depends on other classes. After compiling this class, the dependent class changed its class definition without recompiling all classes, which led to an error.

java.lang.NoClassDefFoundError

Class definition error not found. This error is raised when a Java virtual machine or class loader attempts to instantiate a class, but the definition of the class cannot be found.

java.lang.NoSuchFieldError

There are no errors in the domain. This error is raised when an application tries to access or modify a domain of a class, but there is no definition of the domain in the definition of the class.

java.lang.NoSuchMethodError

There is no error in the method. This error is raised when an application attempts to call a method of a class, but there is no definition of the method in the definition of the class.

java.lang.OutOfMemoryError

Out of memory error. This error is raised when the Java virtual machine does not have enough available memory to allocate to the object.

java.lang.StackOverflowError

Stack overflow error. This error is raised when the application recursively calls too deep and the stack overflows.

java.lang.ThreadDeath

End of thread. This error is raised when the stop method of the Thread class is called to indicate the end of the thread.

Java. lang. unknown error

Unknown error. Used to indicate that the Java virtual machine has an unknown serious error.

java.lang.UnsatisfiedLinkError

Unsatisfied link error. Thrown when a Java virtual machine cannot find the native language definition of a class declared as a native method.

Java . lang . unsupportedclassversionerror

Wrong version of unsupported class. This error occurs when a Java virtual machine attempts to read a class file from, but finds that the current Java virtual machine does not support the major and minor version numbers of the file.

java.lang.VerifyError

Validation error. This error is raised when the validator detects an internal incompatibility or security problem in the class file.

java.lang.VirtualMachineError

Virtual machine error. Used to indicate that the virtual machine is damaged or insufficient resources are needed to continue operation.

java.lang.ArithmeticException

The arithmetic condition is abnormal. For example: integer divided by zero, etc.

Java . lang . arrayindexoutofboundsexception

Array index out of bounds exception. Thrown when the index value of the array is negative or greater than or equal to the array size.

java.lang.ArrayStoreException

Array storage exception. Raised when an object of a non-array declaration type is stored in an array.

java.lang.ClassCastException

Class modeling is not normal. Suppose there are classes A and B(A is not the parent or subclass of B), and O is an instance of A. When O is forcibly constructed as an instance of class B, this exception will be thrown ... This exception is usually called a cast exception.

Java . lang . classnotfoundexception

Class exception not found. This exception is thrown when an application tries to construct a class based on the class name in the form of a string, but it cannot find a class file with the corresponding name after traversing the CLASSPAH.

Java . lang . clonenotsupportedexception

Clone exception is not supported. When the Cloneable interface is not implemented or does not support the clone method, calling its clone () method will throw this exception.

Java . lang . enumconstantnotpresentexception

Enumeration constants have no exceptions. This exception is thrown when an application attempts to access an enumerated object by name and enumeration type, but the enumerated object does not contain constants.

abnormal

Root anomaly. Used to describe what the application wants to capture.

Java . lang . illegalaccessexception

Illegal access exception. This exception is thrown when an application attempts to create an instance of a class through reflection, access its properties, and call its methods, but the definition of the class, property, method, or constructor cannot be accessed at this time.

Java . lang . illegalmonitorstateexception

Illegal monitoring status is abnormal. This exception is thrown when a thread tries to wait for the monitor of an object (O) that does not belong to it or notifies other threads to wait for the monitor of the object (O).

Java . lang . illegalstateexception

Illegal state is abnormal. This exception is thrown when the Java environment and applications are not calling methods in a legal calling state.

Java . lang . illegalthreadstateexception

Illegal thread status is abnormal. When the county is not in the legal calling state of the method and the method is called, an exception will be thrown.

Java . lang . indexoutofboundsexception

Index out of bounds exception. This exception is thrown when the index value of the access sequence is less than 0 or greater than or equal to the sequence size.

Java . lang . instantiation exception

Instantiate an exception. This exception is thrown when you try to create an instance of a class through the newInstance () method, and the class is an abstract class or interface.

Java. lang. interrupted exception

Abort abnormally. This exception is thrown when a Thread is in a long waiting, sleeping or other suspended state, and other threads terminate the thread through the interrupt method of Thread.

Java . lang . negative arraysizeexception

Negative array size is abnormal. This exception is thrown when an array is created with a negative size value.

java.lang.NoSuchFieldException

There are no exceptions in the property. This exception is thrown when a nonexistent class property is accessed.

Java . lang . nosuchmethodexception

There are no exceptions in the method. This exception is thrown when accessing a nonexistent class method.

java.lang.NullPointerException

Null pointer exception. This exception is thrown when an application attempts to use null where an object is expected. For example, call the instance method of null object, access the properties of null object, calculate the length of null object, throw null with throw statement and so on.

Java . lang . numberformatexception

The number format is not normal. This exception is thrown when an attempt is made to convert a string to the specified numeric type, but the string does not conform to the format required by the numeric value type.

java.lang.RuntimeException

Runtime exception. Is the parent class of exceptions that can be thrown during the normal operation of all Java virtual machines.

Exception in java.lang.security.

Security anomaly. An exception thrown by the security manager to indicate a security violation.

Java . lang . stringindexoutofboundsexception

Exception in string index out of bounds. This exception is thrown when characters in a string are accessed with an index value less than 0 or greater than or equal to the sequence size.

Java . lang . typenotpresentexception

There are no exceptions to types.