org.mvel2.asm.Symbol Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of tbel Show documentation
Show all versions of tbel Show documentation
TBEL is a powerful expression language for ThingsBoard platform user-defined functions.
Original implementation is based on MVEL.
// ASM: a very small and fast Java bytecode manipulation framework
// Copyright (c) 2000-2011 INRIA, France Telecom
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// 3. Neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
// THE POSSIBILITY OF SUCH DAMAGE.
package org.mvel2.asm;
/**
* An entry of the constant pool, of the BootstrapMethods attribute, or of the (ASM specific) type
* table of a class.
*
* @see JVMS
* 4.4
* @see JVMS
* 4.7.23
* @author Eric Bruneton
*/
abstract class Symbol {
// Tag values for the constant pool entries (using the same order as in the JVMS).
/** The tag value of CONSTANT_Class_info JVMS structures. */
static final int CONSTANT_CLASS_TAG = 7;
/** The tag value of CONSTANT_Fieldref_info JVMS structures. */
static final int CONSTANT_FIELDREF_TAG = 9;
/** The tag value of CONSTANT_Methodref_info JVMS structures. */
static final int CONSTANT_METHODREF_TAG = 10;
/** The tag value of CONSTANT_InterfaceMethodref_info JVMS structures. */
static final int CONSTANT_INTERFACE_METHODREF_TAG = 11;
/** The tag value of CONSTANT_String_info JVMS structures. */
static final int CONSTANT_STRING_TAG = 8;
/** The tag value of CONSTANT_Integer_info JVMS structures. */
static final int CONSTANT_INTEGER_TAG = 3;
/** The tag value of CONSTANT_Float_info JVMS structures. */
static final int CONSTANT_FLOAT_TAG = 4;
/** The tag value of CONSTANT_Long_info JVMS structures. */
static final int CONSTANT_LONG_TAG = 5;
/** The tag value of CONSTANT_Double_info JVMS structures. */
static final int CONSTANT_DOUBLE_TAG = 6;
/** The tag value of CONSTANT_NameAndType_info JVMS structures. */
static final int CONSTANT_NAME_AND_TYPE_TAG = 12;
/** The tag value of CONSTANT_Utf8_info JVMS structures. */
static final int CONSTANT_UTF8_TAG = 1;
/** The tag value of CONSTANT_MethodHandle_info JVMS structures. */
static final int CONSTANT_METHOD_HANDLE_TAG = 15;
/** The tag value of CONSTANT_MethodType_info JVMS structures. */
static final int CONSTANT_METHOD_TYPE_TAG = 16;
/** The tag value of CONSTANT_Dynamic_info JVMS structures. */
static final int CONSTANT_DYNAMIC_TAG = 17;
/** The tag value of CONSTANT_InvokeDynamic_info JVMS structures. */
static final int CONSTANT_INVOKE_DYNAMIC_TAG = 18;
/** The tag value of CONSTANT_Module_info JVMS structures. */
static final int CONSTANT_MODULE_TAG = 19;
/** The tag value of CONSTANT_Package_info JVMS structures. */
static final int CONSTANT_PACKAGE_TAG = 20;
// Tag values for the BootstrapMethods attribute entries (ASM specific tag).
/** The tag value of the BootstrapMethods attribute entries. */
static final int BOOTSTRAP_METHOD_TAG = 64;
// Tag values for the type table entries (ASM specific tags).
/** The tag value of a normal type entry in the (ASM specific) type table of a class. */
static final int TYPE_TAG = 128;
/**
* The tag value of an {@link Frame#ITEM_UNINITIALIZED} type entry in the type table of a class.
*/
static final int UNINITIALIZED_TYPE_TAG = 129;
/** The tag value of a merged type entry in the (ASM specific) type table of a class. */
static final int MERGED_TYPE_TAG = 130;
// Instance fields.
/**
* The index of this symbol in the constant pool, in the BootstrapMethods attribute, or in the
* (ASM specific) type table of a class (depending on the {@link #tag} value).
*/
final int index;
/**
* A tag indicating the type of this symbol. Must be one of the static tag values defined in this
* class.
*/
final int tag;
/**
* The internal name of the owner class of this symbol. Only used for {@link
* #CONSTANT_FIELDREF_TAG}, {@link #CONSTANT_METHODREF_TAG}, {@link
* #CONSTANT_INTERFACE_METHODREF_TAG}, and {@link #CONSTANT_METHOD_HANDLE_TAG} symbols.
*/
final String owner;
/**
* The name of the class field or method corresponding to this symbol. Only used for {@link
* #CONSTANT_FIELDREF_TAG}, {@link #CONSTANT_METHODREF_TAG}, {@link
* #CONSTANT_INTERFACE_METHODREF_TAG}, {@link #CONSTANT_NAME_AND_TYPE_TAG}, {@link
* #CONSTANT_METHOD_HANDLE_TAG}, {@link #CONSTANT_DYNAMIC_TAG} and {@link
* #CONSTANT_INVOKE_DYNAMIC_TAG} symbols.
*/
final String name;
/**
* The string value of this symbol. This is:
*
*
* - a field or method descriptor for {@link #CONSTANT_FIELDREF_TAG}, {@link
* #CONSTANT_METHODREF_TAG}, {@link #CONSTANT_INTERFACE_METHODREF_TAG}, {@link
* #CONSTANT_NAME_AND_TYPE_TAG}, {@link #CONSTANT_METHOD_HANDLE_TAG}, {@link
* #CONSTANT_METHOD_TYPE_TAG}, {@link #CONSTANT_DYNAMIC_TAG} and {@link
* #CONSTANT_INVOKE_DYNAMIC_TAG} symbols,
*
- an arbitrary string for {@link #CONSTANT_UTF8_TAG} and {@link #CONSTANT_STRING_TAG}
* symbols,
*
- an internal class name for {@link #CONSTANT_CLASS_TAG}, {@link #TYPE_TAG} and {@link
* #UNINITIALIZED_TYPE_TAG} symbols,
*
- {@literal null} for the other types of symbol.
*
*/
final String value;
/**
* The numeric value of this symbol. This is:
*
*
* - the symbol's value for {@link #CONSTANT_INTEGER_TAG},{@link #CONSTANT_FLOAT_TAG}, {@link
* #CONSTANT_LONG_TAG}, {@link #CONSTANT_DOUBLE_TAG},
*
- the CONSTANT_MethodHandle_info reference_kind field value for {@link
* #CONSTANT_METHOD_HANDLE_TAG} symbols,
*
- the CONSTANT_InvokeDynamic_info bootstrap_method_attr_index field value for {@link
* #CONSTANT_INVOKE_DYNAMIC_TAG} symbols,
*
- the offset of a bootstrap method in the BootstrapMethods boostrap_methods array, for
* {@link #CONSTANT_DYNAMIC_TAG} or {@link #BOOTSTRAP_METHOD_TAG} symbols,
*
- the bytecode offset of the NEW instruction that created an {@link
* Frame#ITEM_UNINITIALIZED} type for {@link #UNINITIALIZED_TYPE_TAG} symbols,
*
- the indices (in the class' type table) of two {@link #TYPE_TAG} source types for {@link
* #MERGED_TYPE_TAG} symbols,
*
- 0 for the other types of symbol.
*
*/
final long data;
/**
* Additional information about this symbol, generally computed lazily. Warning: the value of
* this field is ignored when comparing Symbol instances (to avoid duplicate entries in a
* SymbolTable). Therefore, this field should only contain data that can be computed from the
* other fields of this class. It contains:
*
*
* - the {@link Type#getArgumentsAndReturnSizes} of the symbol's method descriptor for {@link
* #CONSTANT_METHODREF_TAG}, {@link #CONSTANT_INTERFACE_METHODREF_TAG} and {@link
* #CONSTANT_INVOKE_DYNAMIC_TAG} symbols,
*
- the index in the InnerClasses_attribute 'classes' array (plus one) corresponding to this
* class, for {@link #CONSTANT_CLASS_TAG} symbols,
*
- the index (in the class' type table) of the merged type of the two source types for
* {@link #MERGED_TYPE_TAG} symbols,
*
- 0 for the other types of symbol, or if this field has not been computed yet.
*
*/
int info;
/**
* Constructs a new Symbol. This constructor can't be used directly because the Symbol class is
* abstract. Instead, use the factory methods of the {@link SymbolTable} class.
*
* @param index the symbol index in the constant pool, in the BootstrapMethods attribute, or in
* the (ASM specific) type table of a class (depending on 'tag').
* @param tag the symbol type. Must be one of the static tag values defined in this class.
* @param owner The internal name of the symbol's owner class. Maybe {@literal null}.
* @param name The name of the symbol's corresponding class field or method. Maybe {@literal
* null}.
* @param value The string value of this symbol. Maybe {@literal null}.
* @param data The numeric value of this symbol.
*/
Symbol(
final int index,
final int tag,
final String owner,
final String name,
final String value,
final long data) {
this.index = index;
this.tag = tag;
this.owner = owner;
this.name = name;
this.value = value;
this.data = data;
}
/**
* Returns the result {@link Type#getArgumentsAndReturnSizes} on {@link #value}.
*
* @return the result {@link Type#getArgumentsAndReturnSizes} on {@link #value} (memoized in
* {@link #info} for efficiency). This should only be used for {@link
* #CONSTANT_METHODREF_TAG}, {@link #CONSTANT_INTERFACE_METHODREF_TAG} and {@link
* #CONSTANT_INVOKE_DYNAMIC_TAG} symbols.
*/
int getArgumentsAndReturnSizes() {
if (info == 0) {
info = Type.getArgumentsAndReturnSizes(value);
}
return info;
}
}