1876 words

javax.persistence.NonUniqueResultException - JPA exception

javax.persistence
Exception NonUniqueResultException

java.lang.Object
    java.lang.Throwable
        java.lang.Exception
            java.lang.RuntimeException
                javax.persistence.PersistenceException
                    javax.persistence.NonUniqueResultException
Implemented Interfaces:
Serializable
Thrown by the persistence provider when Query.getSingleResult() or TypedQuery.getSingleResult() is executed on a query and there is more than one result from the query. This exception will not cause the current transaction, if one is active, to be marked for rollback.
Since:
JPA 1.0
See Also:
Query.getSingleResult()
TypedQuery.getSingleResult()
Constructs a new NonUniqueResultException exception with null as its detail message.
Constructs a new NonUniqueResultException exception with null as its detail message.
Since:
JPA 1.0
NonUniqueResultException(String message)
Constructs a new NonUniqueResultException exception with the specified detail message.
Constructs a new NonUniqueResultException exception with the specified detail message.
Parameters:
message - the detail message.
Since:
JPA 1.0
Throwable fillInStackTrace()
Fills in the execution stack trace.
Fills in the execution stack trace. This method records within this Throwable object information about the current state of the stack frames for the current thread.
Returns:
a reference to this Throwable instance.
Since:
Java JDK1.0
See Also:
java.lang.Throwable.printStackTrace()
Throwable getCause()
Returns the cause of this throwable or null if the cause is nonexistent or unknown.
Returns the cause of this throwable or null if the cause is nonexistent or unknown. (The cause is the throwable that caused this throwable to get thrown.)

This implementation returns the cause that was supplied via one of the constructors requiring a Throwable, or that was set after creation with the initCause(Throwable) method. While it is typically unnecessary to override this method, a subclass can override it to return a cause set by some other means. This is appropriate for a "legacy chained throwable" that predates the addition of chained exceptions to Throwable. Note that it is not necessary to override any of the PrintStackTrace methods, all of which invoke the getCause method to determine the cause of a throwable.

Returns:
the cause of this throwable or null if the cause is nonexistent or unknown.
Since:
Java 1.4
String getLocalizedMessage()
Creates a localized description of this throwable.
Creates a localized description of this throwable. Subclasses may override this method in order to produce a locale-specific message. For subclasses that do not override this method, the default implementation returns the same result as getMessage().
Returns:
The localized description of this throwable.
Since:
Java JDK1.1
String getMessage()
Returns the detail message string of this throwable.
Returns the detail message string of this throwable.
Returns:
the detail message string of this Throwable instance (which may be null).
Since:
Java JDK1.0
StackTraceElement[] getStackTrace()
Provides programmatic access to the stack trace information printed by printStackTrace().
Provides programmatic access to the stack trace information printed by printStackTrace(). Returns an array of stack trace elements, each representing one stack frame. The zeroth element of the array (assuming the array's length is non-zero) represents the top of the stack, which is the last method invocation in the sequence. Typically, this is the point at which this throwable was created and thrown. The last element of the array (assuming the array's length is non-zero) represents the bottom of the stack, which is the first method invocation in the sequence.

Some virtual machines may, under some circumstances, omit one or more stack frames from the stack trace. In the extreme case, a virtual machine that has no stack trace information concerning this throwable is permitted to return a zero-length array from this method. Generally speaking, the array returned by this method will contain one element for every frame that would be printed by printStackTrace.

Returns:
an array of stack trace elements representing the stack trace pertaining to this throwable.
Since:
Java 1.4
Throwable initCause(Throwable cause)
Initializes the cause of this throwable to the specified value.
Initializes the cause of this throwable to the specified value. (The cause is the throwable that caused this throwable to get thrown.)

This method can be called at most once. It is generally called from within the constructor, or immediately after creating the throwable. If this throwable was created with Throwable(Throwable) or Throwable(String,Throwable), this method cannot be called even once.

Parameters:
cause - the cause (which is saved for later retrieval by the getCause() method). (A null value is permitted, and indicates that the cause is nonexistent or unknown.)
Returns:
a reference to this Throwable instance.
Throws:
IllegalArgumentException - if cause is this throwable. (A throwable cannot be its own cause.)
IllegalStateException - if this throwable was created with Throwable(Throwable) or Throwable(String,Throwable), or this method has already been called on this throwable.
Since:
Java 1.4
void printStackTrace()
Prints this throwable and its backtrace to the standard error stream.
Prints this throwable and its backtrace to the standard error stream. This method prints a stack trace for this Throwable object on the error output stream that is the value of the field System.err. The first line of output contains the result of the toString() method for this object. Remaining lines represent data previously recorded by the method fillInStackTrace(). The format of this information depends on the implementation, but the following example may be regarded as typical:
 java.lang.NullPointerException
         at MyClass.mash(MyClass.java:9)
         at MyClass.crunch(MyClass.java:6)
         at MyClass.main(MyClass.java:3)
This example was produced by running the program:
 class MyClass {
     public static void main(String[] args) {
         crunch(null);
     }
     static void crunch(int[] a) {
         mash(a);
     }
     static void mash(int[] b) {
         System.out.println(b[0]);
     }
 }
The backtrace for a throwable with an initialized, non-null cause should generally include the backtrace for the cause. The format of this information depends on the implementation, but the following example may be regarded as typical:
 HighLevelException: MidLevelException: LowLevelException
         at Junk.a(Junk.java:13)
         at Junk.main(Junk.java:4)
 Caused by: MidLevelException: LowLevelException
         at Junk.c(Junk.java:23)
         at Junk.b(Junk.java:17)
         at Junk.a(Junk.java:11)
         ... 1 more
 Caused by: LowLevelException
         at Junk.e(Junk.java:30)
         at Junk.d(Junk.java:27)
         at Junk.c(Junk.java:21)
         ... 3 more
Note the presence of lines containing the characters "...". These lines indicate that the remainder of the stack trace for this exception matches the indicated number of frames from the bottom of the stack trace of the exception that was caused by this exception (the "enclosing" exception). This shorthand can greatly reduce the length of the output in the common case where a wrapped exception is thrown from same method as the "causative exception" is caught. The above example was produced by running the program:
 public class Junk {
     public static void main(String args[]) {
         try {
             a();
         } catch(HighLevelException e) {
             e.printStackTrace();
         }
     }
     static void a() throws HighLevelException {
         try {
             b();
         } catch(MidLevelException e) {
             throw new HighLevelException(e);
         }
     }
     static void b() throws MidLevelException {
         c();
     }
     static void c() throws MidLevelException {
         try {
             d();
         } catch(LowLevelException e) {
             throw new MidLevelException(e);
         }
     }
     static void d() throws LowLevelException {
        e();
     }
     static void e() throws LowLevelException {
         throw new LowLevelException();
     }
 }
 
 class HighLevelException extends Exception {
     HighLevelException(Throwable cause) { super(cause); }
 }
 
 class MidLevelException extends Exception {
     MidLevelException(Throwable cause)  { super(cause); }
 }
 
 class LowLevelException extends Exception {
 }
Since:
Java JDK1.0
void printStackTrace(PrintStream s)
Prints this throwable and its backtrace to the specified print stream.
Prints this throwable and its backtrace to the specified print stream.
Parameters:
s - PrintStream to use for output
Since:
Java JDK1.0
void printStackTrace(PrintWriter s)
Prints this throwable and its backtrace to the specified print writer.
Prints this throwable and its backtrace to the specified print writer.
Parameters:
s - PrintWriter to use for output
Since:
Java JDK1.1
void setStackTrace(StackTraceElement[] stackTrace)
Sets the stack trace elements that will be returned by getStackTrace() and printed by printStackTrace() and related methods.
Sets the stack trace elements that will be returned by getStackTrace() and printed by printStackTrace() and related methods. This method, which is designed for use by RPC frameworks and other advanced systems, allows the client to override the default stack trace that is either generated by fillInStackTrace() when a throwable is constructed or deserialized when a throwable is read from a serialization stream.
Parameters:
stackTrace - the stack trace elements to be associated with this Throwable. The specified array is copied by this call; changes in the specified array after the method invocation returns will have no affect on this Throwable's stack trace.
Throws:
NullPointerException - if stackTrace is null, or if any of the elements of stackTrace are null
Since:
Java 1.4
String toString()
Returns a short description of this throwable.
Returns a short description of this throwable. The result is the concatenation of:
  • the name of the class of this object
  • ": " (a colon and a space)
  • the result of invoking this object's getLocalizedMessage method
If getLocalizedMessage returns null, then just the class name is returned.
Returns:
a string representation of this throwable.
Since:
Java JDK1.0

This documentation page is derived (with some adjustments) from the open source JPA 2 RI (EclipseLink)
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
Object Relational Mapping (ORM) JPA 2 providers include Hibernate, EclipseLink, TopLink, OpenJPA and DataNucleus.
Object DB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.