Summary

Add a new utility method, ClassEntry::equalsSymbol(ClassDesc), to facilitate easy comparison of ClassEntry with ClassDesc constants.

Problem

ClassEntry is often compared against desired classes during bytecode transformation, such as ce.name().equalsString("java/lang/System") if we want to detect if a call is to System::exit.

However, we intend to reduce the use of "internal names" which is a legacy baggage. Such internal names are not available as constants, so writing them manually is error-prone.

We have constants for ClassDesc, but the current way to compare ClassEntry to ClassDesc is ce.asSymbol().equals(cd). This approach has a few problems:

1. The conversion of ClassEntry to ClassDesc via asSymbol involves unnecessary transformations and is performance-wise undesirable.
2. If the ClassEntry points to a Utf8Entry with invalid content, asSymbol will unexpectedly fail.

Solution

To facilitate good programming habits with the ClassFile API, we need a new ClassEntry::equalsSymbol(ClassDesc), which:

1. Allows usage of known constants, such as equalsSymbol(CD_System);
2. Is as efficient as name().equalsString("java/lang/System");
3. Does not fail if the ClassEntry itself is invalid.

Specification

    /**
     * {@return whether this class entry describes the same class as the provided symbol}
     *
     * @param symbol the symbol to compare to
     */
    boolean equalsSymbol(ClassDesc symbol);