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package jdk.internal.reflect;

import java.lang.reflect.*;
import java.util.Set;

Provides reflective access to the constant pools of classes. Currently this is needed to provide reflective access to annotations but may be used by other internal subsystems in the future.
/** Provides reflective access to the constant pools of classes. Currently this is needed to provide reflective access to annotations but may be used by other internal subsystems in the future. */
public class ConstantPool { // Number of entries in this constant pool (= maximum valid constant pool index) public int getSize() { return getSize0 (constantPoolOop); } public Class<?> getClassAt (int index) { return getClassAt0 (constantPoolOop, index); } public Class<?> getClassAtIfLoaded (int index) { return getClassAtIfLoaded0 (constantPoolOop, index); } // Returns a class reference index for a method or a field. public int getClassRefIndexAt(int index) { return getClassRefIndexAt0(constantPoolOop, index); } // Returns either a Method or Constructor. // Static initializers are returned as Method objects. public Member getMethodAt (int index) { return getMethodAt0 (constantPoolOop, index); } public Member getMethodAtIfLoaded(int index) { return getMethodAtIfLoaded0(constantPoolOop, index); } public Field getFieldAt (int index) { return getFieldAt0 (constantPoolOop, index); } public Field getFieldAtIfLoaded (int index) { return getFieldAtIfLoaded0 (constantPoolOop, index); } // Fetches the class name, member (field, method or interface // method) name, and type descriptor as an array of three Strings public String[] getMemberRefInfoAt (int index) { return getMemberRefInfoAt0 (constantPoolOop, index); } // Returns a name and type reference index for a method, a field or an invokedynamic. public int getNameAndTypeRefIndexAt(int index) { return getNameAndTypeRefIndexAt0(constantPoolOop, index); } // Fetches the name and type from name_and_type index as an array of two Strings public String[] getNameAndTypeRefInfoAt(int index) { return getNameAndTypeRefInfoAt0(constantPoolOop, index); } public int getIntAt (int index) { return getIntAt0 (constantPoolOop, index); } public long getLongAt (int index) { return getLongAt0 (constantPoolOop, index); } public float getFloatAt (int index) { return getFloatAt0 (constantPoolOop, index); } public double getDoubleAt (int index) { return getDoubleAt0 (constantPoolOop, index); } public String getStringAt (int index) { return getStringAt0 (constantPoolOop, index); } public String getUTF8At (int index) { return getUTF8At0 (constantPoolOop, index); } public Tag getTagAt(int index) { return Tag.valueOf(getTagAt0(constantPoolOop, index)); } public static enum Tag { UTF8(1), INTEGER(3), FLOAT(4), LONG(5), DOUBLE(6), CLASS(7), STRING(8), FIELDREF(9), METHODREF(10), INTERFACEMETHODREF(11), NAMEANDTYPE(12), METHODHANDLE(15), METHODTYPE(16), INVOKEDYNAMIC(18), INVALID(0); private final int tagCode; private Tag(int tagCode) { this.tagCode = tagCode; } private static Tag valueOf(byte v) { for (Tag tag : Tag.values()) { if (tag.tagCode == v) { return tag; } } throw new IllegalArgumentException("Unknown constant pool tag code " + v); } } //--------------------------------------------------------------------------- // Internals only below this point // static { Reflection.registerFieldsToFilter(ConstantPool.class, Set.of("constantPoolOop")); } // HotSpot-internal constant pool object (set by the VM, name known to the VM) private Object constantPoolOop; private native int getSize0 (Object constantPoolOop); private native Class<?> getClassAt0 (Object constantPoolOop, int index); private native Class<?> getClassAtIfLoaded0 (Object constantPoolOop, int index); private native int getClassRefIndexAt0 (Object constantPoolOop, int index); private native Member getMethodAt0 (Object constantPoolOop, int index); private native Member getMethodAtIfLoaded0(Object constantPoolOop, int index); private native Field getFieldAt0 (Object constantPoolOop, int index); private native Field getFieldAtIfLoaded0 (Object constantPoolOop, int index); private native String[] getMemberRefInfoAt0 (Object constantPoolOop, int index); private native int getNameAndTypeRefIndexAt0(Object constantPoolOop, int index); private native String[] getNameAndTypeRefInfoAt0(Object constantPoolOop, int index); private native int getIntAt0 (Object constantPoolOop, int index); private native long getLongAt0 (Object constantPoolOop, int index); private native float getFloatAt0 (Object constantPoolOop, int index); private native double getDoubleAt0 (Object constantPoolOop, int index); private native String getStringAt0 (Object constantPoolOop, int index); private native String getUTF8At0 (Object constantPoolOop, int index); private native byte getTagAt0 (Object constantPoolOop, int index); }