Query (Java SE 15 & JDK 15) (original) (raw)

public class Query extends Object

Constructs query object constraints.

The MBean Server can be queried for MBeans that meet a particular condition, using its queryNames orqueryMBeans method. The QueryExp parameter to the method can be any implementation of the interfaceQueryExp, but it is usually best to obtain the QueryExp value by calling the static methods in this class. This is particularly true when querying a remote MBean Server: a custom implementation of theQueryExp interface might not be present in the remote MBean Server, but the methods in this class return only standard classes that are part of the JMX implementation.

As an example, suppose you wanted to find all MBeans where the Enabled attribute is true and the Owner attribute is "Duke". Here is how you could construct the appropriate QueryExp by chaining together method calls:

QueryExp query = Query.and(Query.eq(Query.attr("Enabled"), Query.value(true)), Query.eq(Query.attr("Owner"), Query.value("Duke")));

Since:

1.5

• Field Summary

Fields

• Constructor Summary

Constructors

• Method Summary

Methods declared in class java.lang.Object

[clone](../../../java.base/java/lang/Object.html#clone%28%29), [equals](../../../java.base/java/lang/Object.html#equals%28java.lang.Object%29), [finalize](../../../java.base/java/lang/Object.html#finalize%28%29), [getClass](../../../java.base/java/lang/Object.html#getClass%28%29), [hashCode](../../../java.base/java/lang/Object.html#hashCode%28%29), [notify](../../../java.base/java/lang/Object.html#notify%28%29), [notifyAll](../../../java.base/java/lang/Object.html#notifyAll%28%29), [toString](../../../java.base/java/lang/Object.html#toString%28%29), [wait](../../../java.base/java/lang/Object.html#wait%28%29), [wait](../../../java.base/java/lang/Object.html#wait%28long%29), [wait](../../../java.base/java/lang/Object.html#wait%28long,int%29)

• Field Details

  • GT

  public static final int GT
  A code representing the gt(javax.management.ValueExp, javax.management.ValueExp) query. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • LT

  public static final int LT
  A code representing the lt(javax.management.ValueExp, javax.management.ValueExp) query. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • GE

  public static final int GE
  A code representing the geq(javax.management.ValueExp, javax.management.ValueExp) query. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • LE

  public static final int LE
  A code representing the leq(javax.management.ValueExp, javax.management.ValueExp) query. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • EQ

  public static final int EQ
  A code representing the eq(javax.management.ValueExp, javax.management.ValueExp) query. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • PLUS

  public static final int PLUS
  A code representing the plus(javax.management.ValueExp, javax.management.ValueExp) expression. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • MINUS

  public static final int MINUS
  A code representing the minus(javax.management.ValueExp, javax.management.ValueExp) expression. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • TIMES

  public static final int TIMES
  A code representing the times(javax.management.ValueExp, javax.management.ValueExp) expression. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

  • DIV

  public static final int DIV
  A code representing the div(javax.management.ValueExp, javax.management.ValueExp) expression. This is chiefly of interest for the serialized form of queries.
  See Also:
  Constant Field Values

• Constructor Details

  • Query

  public Query()
  Basic constructor.

• Method Details

  • and

  Returns a query expression that is the conjunction of two other query expressions.
  Parameters:
  q1 - A query expression.
  q2 - Another query expression.
  Returns:
  The conjunction of the two arguments. The returned object will be serialized as an instance of the non-public class javax.management.AndQueryExp.

  • or

  Returns a query expression that is the disjunction of two other query expressions.
  Parameters:
  q1 - A query expression.
  q2 - Another query expression.
  Returns:
  The disjunction of the two arguments. The returned object will be serialized as an instance of the non-public class javax.management.OrQueryExp.

  • gt

  Returns a query expression that represents a "greater than" constraint on two values.
  Parameters:
  v1 - A value expression.
  v2 - Another value expression.
  Returns:
  A "greater than" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a relOp equal to GT.

  • geq

  Returns a query expression that represents a "greater than or equal to" constraint on two values.
  Parameters:
  v1 - A value expression.
  v2 - Another value expression.
  Returns:
  A "greater than or equal to" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a relOp equal to GE.

  • leq

  Returns a query expression that represents a "less than or equal to" constraint on two values.
  Parameters:
  v1 - A value expression.
  v2 - Another value expression.
  Returns:
  A "less than or equal to" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a relOp equal to LE.

  • lt

  Returns a query expression that represents a "less than" constraint on two values.
  Parameters:
  v1 - A value expression.
  v2 - Another value expression.
  Returns:
  A "less than" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a relOp equal to LT.

  • eq

  Returns a query expression that represents an equality constraint on two values.
  Parameters:
  v1 - A value expression.
  v2 - Another value expression.
  Returns:
  A "equal to" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a relOp equal to EQ.

  • between

  Returns a query expression that represents the constraint that one value is between two other values.
  Parameters:
  v1 - A value expression that is "between" v2 and v3.
  v2 - Value expression that represents a boundary of the constraint.
  v3 - Value expression that represents a boundary of the constraint.
  Returns:
  The constraint that v1 lies between v2 and v3. The returned object will be serialized as an instance of the non-public class javax.management.BetweenQueryExp.

  • match

  Returns a query expression that represents a matching constraint on a string argument. The matching syntax is consistent with file globbing: supports "?", "*", "[", each of which may be escaped with "\"; character classes may use "!" for negation and "-" for range. (* for any character sequence,? for a single arbitrary character,[...] for a character sequence). For example: a*b?c would match a string starting with the character a, followed by any number of characters, followed by a b, any single character, and a c.
  Parameters:
  a - An attribute expression
  s - A string value expression representing a matching constraint
  Returns:
  A query expression that represents the matching constraint on the string argument. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  • attr

  Parameters:
  name - The name of the attribute.
  Returns:
  An attribute expression for the attribute named name.

  • attr

  Parameters:
  className - The name of the class possessing the attribute.
  name - The name of the attribute.
  Returns:
  An attribute expression for the attribute named name. The returned object will be serialized as an instance of the non-public class javax.management.QualifiedAttributeValueExp.

  • classattr

  Returns a new class attribute expression which can be used in any Query call that expects a ValueExp.
  Evaluating this expression for a givenobjectName includes performing MBeanServer.getObjectInstance(objectName).
  Returns:
  A class attribute expression. The returned object will be serialized as an instance of the non-public class javax.management.ClassAttributeValueExp.

  • not

  Returns a constraint that is the negation of its argument.
  Parameters:
  queryExp - The constraint to negate.
  Returns:
  A negated constraint. The returned object will be serialized as an instance of the non-public class javax.management.NotQueryExp.

  • in

  Returns an expression constraining a value to be one of an explicit list.
  Parameters:
  val - A value to be constrained.
  valueList - An array of ValueExps.
  Returns:
  A QueryExp that represents the constraint. The returned object will be serialized as an instance of the non-public class javax.management.InQueryExp.

  • value

  Returns a new string expression.
  Parameters:
  val - The string value.
  Returns:
  A ValueExp object containing the string argument.

  • value

  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  Parameters:
  val - An instance of Number.
  Returns:
  A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  • value

  public static ValueExp value​(int val)
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  Parameters:
  val - An int value.
  Returns:
  A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  • value

  public static ValueExp value​(long val)
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  Parameters:
  val - A long value.
  Returns:
  A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  • value

  public static ValueExp value​(float val)
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  Parameters:
  val - A float value.
  Returns:
  A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  • value

  public static ValueExp value​(double val)
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  Parameters:
  val - A double value.
  Returns:
  A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  • value

  public static ValueExp value​(boolean val)
  Returns a boolean value expression that can be used in any Query call that expects a ValueExp.
  Parameters:
  val - A boolean value.
  Returns:
  A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.BooleanValueExp.

  • plus

  Returns a binary expression representing the sum of two numeric values, or the concatenation of two string values.
  Parameters:
  value1 - The first '+' operand.
  value2 - The second '+' operand.
  Returns:
  A ValueExp representing the sum or concatenation of the two arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an op equal toPLUS.

  • times

  Returns a binary expression representing the product of two numeric values.
  Parameters:
  value1 - The first '*' operand.
  value2 - The second '*' operand.
  Returns:
  A ValueExp representing the product. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an op equal toTIMES.

  • minus

  Returns a binary expression representing the difference between two numeric values.
  Parameters:
  value1 - The first '-' operand.
  value2 - The second '-' operand.
  Returns:
  A ValueExp representing the difference between two arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an op equal toMINUS.

  • div

  Returns a binary expression representing the quotient of two numeric values.
  Parameters:
  value1 - The first '/' operand.
  value2 - The second '/' operand.
  Returns:
  A ValueExp representing the quotient of two arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an op equal toDIV.

  • initialSubString

  Returns a query expression that represents a matching constraint on a string argument. The value must start with the given literal string value.
  Parameters:
  a - An attribute expression.
  s - A string value expression representing the beginning of the string value.
  Returns:
  The constraint that a matches s. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  • anySubString

  Returns a query expression that represents a matching constraint on a string argument. The value must contain the given literal string value.
  Parameters:
  a - An attribute expression.
  s - A string value expression representing the substring.
  Returns:
  The constraint that a matches s. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  • finalSubString

  Returns a query expression that represents a matching constraint on a string argument. The value must end with the given literal string value.
  Parameters:
  a - An attribute expression.
  s - A string value expression representing the end of the string value.
  Returns:
  The constraint that a matches s. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  • isInstanceOf

  Parameters:
  classNameValue - The StringValueExp returning the name of the class of which selected MBeans should be instances.
  Returns:
  a query expression that represents an inheritance constraint on an MBean class. The returned object will be serialized as an instance of the non-public class javax.management.InstanceOfQueryExp.
  Since:
  1.6