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src/jdk.vm.ci/share/classes/jdk.vm.ci.meta/src/jdk/vm/ci/meta/ConstantReflectionProvider.java

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  39      * {@link Boolean#TRUE true} if the two constants represent the same run time value,
  40      * {@link Boolean#FALSE false} if they are different. Returns {@code null} if the constants
  41      * cannot be compared at this point.
  42      */
  43     Boolean constantEquals(Constant x, Constant y);
  44 
  45     /**
  46      * Returns the length of the array constant. Returns {@code null} if the constant is not an
  47      * array, or if the array length is not available at this point.
  48      */
  49     Integer readArrayLength(JavaConstant array);
  50 
  51     /**
  52      * Reads a value from the given array at the given index. Returns {@code null} if the constant
  53      * is not an array, if the index is out of bounds, or if the value is not available at this
  54      * point.
  55      */
  56     JavaConstant readArrayElement(JavaConstant array, int index);
  57 
  58     /**
  59      * Reads a value from the given array at the given index if it is a stable array. Returns
  60      * {@code null} if the constant is not a stable array, if it is a default value, if the index is
  61      * out of bounds, or if the value is not available at this point.
  62      */
  63     JavaConstant readConstantArrayElement(JavaConstant array, int index);
  64 
  65     /**
  66      * Reads a value from the given array at the given offset if it is a stable array. The offset
  67      * will be decoded relative to the platform addressing into an index into the array. Returns
  68      * {@code null} if the constant is not a stable array, if it is a default value, if the offset
  69      * is out of bounds, or if the value is not available at this point.
  70      */
  71     JavaConstant readConstantArrayElementForOffset(JavaConstant array, long offset);
  72 
  73     /**
  74      * Gets the constant value of this field. Note that a {@code static final} field may not be
  75      * considered constant if its declaring class is not yet initialized or if it is a well known
  76      * field that can be updated via other means (e.g., {@link System#setOut(java.io.PrintStream)}).
  77      *
  78      * @param receiver object from which this field's value is to be read. This value is ignored if
  79      *            this field is static.
  80      * @return the constant value of this field or {@code null} if this field is not considered
  81      *         constant by the runtime
  82      */
  83     JavaConstant readConstantFieldValue(ResolvedJavaField field, JavaConstant receiver);
  84 
  85     /**
  86      * Gets the current value of this field for a given object, if available.
  87      *
  88      * There is no guarantee that the same value will be returned by this method for a field unless
  89      * the field is considered to be
  90      * {@linkplain #readConstantFieldValue(ResolvedJavaField, JavaConstant) constant} by the
  91      * runtime.
  92      *
  93      * @param receiver object from which this field's value is to be read. This value is ignored if
  94      *            this field is static.
  95      * @return the value of this field or {@code null} if the value is not available (e.g., because
  96      *         the field holder is not yet initialized).
  97      */
  98     JavaConstant readFieldValue(ResolvedJavaField field, JavaConstant receiver);
  99 
 100     /**
 101      * Gets the current value of this field for a given object, if available. Like
 102      * {@link #readFieldValue(ResolvedJavaField, JavaConstant)} but treats array fields as stable.
 103      *
 104      * There is no guarantee that the same value will be returned by this method for a field unless
 105      * the field is considered to be
 106      * {@linkplain #readConstantFieldValue(ResolvedJavaField, JavaConstant) constant} by the
 107      * runtime.
 108      *
 109      * @param receiver object from which this field's value is to be read. This value is ignored if
 110      *            this field is static.
 111      * @param isDefaultStable if {@code true}, default values are considered stable
 112      * @return the value of this field or {@code null} if the value is not available (e.g., because
 113      *         the field holder is not yet initialized).
 114      */
 115     JavaConstant readStableFieldValue(ResolvedJavaField field, JavaConstant receiver, boolean isDefaultStable);
 116 
 117     /**
 118      * Converts the given {@link JavaKind#isPrimitive() primitive} constant to a boxed
 119      * {@link JavaKind#Object object} constant, according to the Java boxing rules. Returns
 120      * {@code null} if the source is is not a primitive constant, or the boxed value is not
 121      * available at this point.
 122      */
 123     JavaConstant boxPrimitive(JavaConstant source);
 124 
 125     /**
 126      * Converts the given {@link JavaKind#Object object} constant to a {@link JavaKind#isPrimitive()
 127      * primitive} constant, according to the Java unboxing rules. Returns {@code null} if the source
 128      * is is not an object constant that can be unboxed, or the unboxed value is not available at
 129      * this point.
 130      */
 131     JavaConstant unboxPrimitive(JavaConstant source);
 132 
 133     /**
 134      * Gets a string as a {@link JavaConstant}.
 135      */




  39      * {@link Boolean#TRUE true} if the two constants represent the same run time value,
  40      * {@link Boolean#FALSE false} if they are different. Returns {@code null} if the constants
  41      * cannot be compared at this point.
  42      */
  43     Boolean constantEquals(Constant x, Constant y);
  44 
  45     /**
  46      * Returns the length of the array constant. Returns {@code null} if the constant is not an
  47      * array, or if the array length is not available at this point.
  48      */
  49     Integer readArrayLength(JavaConstant array);
  50 
  51     /**
  52      * Reads a value from the given array at the given index. Returns {@code null} if the constant
  53      * is not an array, if the index is out of bounds, or if the value is not available at this
  54      * point.
  55      */
  56     JavaConstant readArrayElement(JavaConstant array, int index);
  57 
  58     /**



























  59      * Gets the current value of this field for a given object, if available.
  60      *
  61      * There is no guarantee that the same value will be returned by this method for a field unless
  62      * the field is considered to be constant by the runtime.


  63      *
  64      * @param receiver object from which this field's value is to be read. This value is ignored if
  65      *            this field is static.
  66      * @return the value of this field or {@code null} if the value is not available (e.g., because
  67      *         the field holder is not yet initialized).
  68      */
  69     JavaConstant readFieldValue(ResolvedJavaField field, JavaConstant receiver);

















  70 
  71     /**
  72      * Converts the given {@link JavaKind#isPrimitive() primitive} constant to a boxed
  73      * {@link JavaKind#Object object} constant, according to the Java boxing rules. Returns
  74      * {@code null} if the source is is not a primitive constant, or the boxed value is not
  75      * available at this point.
  76      */
  77     JavaConstant boxPrimitive(JavaConstant source);
  78 
  79     /**
  80      * Converts the given {@link JavaKind#Object object} constant to a {@link JavaKind#isPrimitive()
  81      * primitive} constant, according to the Java unboxing rules. Returns {@code null} if the source
  82      * is is not an object constant that can be unboxed, or the unboxed value is not available at
  83      * this point.
  84      */
  85     JavaConstant unboxPrimitive(JavaConstant source);
  86 
  87     /**
  88      * Gets a string as a {@link JavaConstant}.
  89      */


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