FA-90021 / Bytecode virtual machines / Open access
Constant pool: class names keep internal slashes · case 01
Resolved class names print as java/lang/String instead of java.lang.String.
ROOT CAUSE
The Class resolution returns the raw binary name.
THE FAILURE
The Class resolution returns the raw binary name.
Unsuccessful approach: Replacing only the first separator leaves deeper package names half converted.
Case contract
pool lists entries in file order; indexes start at 1 and Long/Double entries occupy two indexes (the second is unusable). Resolution: Utf8 -> text; Integer/Long/Double -> value; String -> quoted Utf8 text; Class -> Utf8 binary name with "/" turned into "."; NameAndType -> "name:descriptor"; Methodref and Fieldref -> "Class.name:descriptor" where the owner must be a Class entry and the second index a NameAndType. Any index that is missing or of the wrong kind yields ["bad-ref", index].
Why this case matters
Class loaders and interpreters must resolve symbolic references against the exact pool layout.
1 / The failure
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(pool, queries):
table = {}
idx = 1
for e in pool:
table[idx] = e
idx += 2 if e[0] in ('Long', 'Double') else 1
def utf(i):
e = table.get(i)
if e is None or e[0] != 'Utf8':
raise LookupError(i)
return e[1]
def res(i):
e = table.get(i)
if e is None:
raise LookupError(i)
kind = e[0]
if kind == 'Utf8':
return e[1]
if kind in ('Integer', 'Long', 'Double'):
return e[1]
if kind == 'String':
return '"' + utf(e[1]) + '"'
if kind == 'Class':
return utf(e[1])
if kind == 'NameAndType':
return utf(e[1]) + ':' + utf(e[2])
if kind in ('Methodref', 'Fieldref'):
c = table.get(e[1])
if c is None or c[0] != 'Class':
raise LookupError(e[1])
n = table.get(e[2])
if n is None or n[0] != 'NameAndType':
raise LookupError(e[2])
return res(e[1]) + '.' + res(e[2])
raise LookupError(i)
out = []
for q in queries:
try:
out.append(res(q))
except LookupError as err:
out.append(['bad-ref', err.args[0]])
return out
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('regression: method reference',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[6]),
['java.lang.String.length1:()I']),
('entries after a Long keep their index',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[9, 8]),
[41, ['bad-ref', 8]]),
('entries after a Double keep their index',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[12, 18]),
['"length1"', 7]),
('field reference',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[13]),
['java.lang.String.length1:()I']),
('method reference with non-Class owner',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[14]),
[['bad-ref', 1]]),
('string constant pointing at an Integer',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[15]),
[['bad-ref', 9]]),
('nested package class name',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[17, 2]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[5]),
['length1:()I']),
('index zero is invalid',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[7]),
['java.lang.String.length2:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[10, 9]),
[42, ['bad-ref', 9]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[13, 19]),
['"length2"', 14]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[14]),
['java.lang.String.length2:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[15]),
[['bad-ref', 2]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[16]),
[['bad-ref', 10]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[18, 3]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[6]),
['length2:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[8]),
['java.lang.String.length3:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[11, 10]),
[43, ['bad-ref', 10]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[14, 20]),
['"length3"', 21]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[15]),
['java.lang.String.length3:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[16]),
[['bad-ref', 3]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[17]),
[['bad-ref', 11]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[19, 4]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[7]),
['length3:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[9]),
['java.lang.String.length4:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[12, 11]),
[44, ['bad-ref', 11]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[15, 21]),
['"length4"', 28]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[16]),
['java.lang.String.length4:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[17]),
[['bad-ref', 4]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[18]),
[['bad-ref', 12]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[20, 5]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[8]),
['length4:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[10]),
['java.lang.String.length5:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[13, 12]),
[45, ['bad-ref', 12]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[16, 22]),
['"length5"', 35]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[17]),
['java.lang.String.length5:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[18]),
[['bad-ref', 5]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[19]),
[['bad-ref', 13]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[21, 6]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[9]),
['length5:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[0]),
[['bad-ref', 0]])]]
for label, args, expected in cases[N - 1]:
check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
| Boundary fixture | Actual | Expected | Outcome |
|---|---|---|---|
| regression: method reference | ['java/lang/String.length1:()I'] | ['java.lang.String.length1:()I'] | Failed |
| entries after a Long keep their index | [41, ['bad-ref', 8]] | [41, ['bad-ref', 8]] | Passed |
| entries after a Double keep their index | ['"length1"', 7] | ['"length1"', 7] | Passed |
| field reference | ['java/lang/String.length1:()I'] | ['java.lang.String.length1:()I'] | Failed |
| method reference with non-Class owner | [['bad-ref', 1]] | [['bad-ref', 1]] | Passed |
| string constant pointing at an Integer | [['bad-ref', 9]] | [['bad-ref', 9]] | Passed |
| nested package class name | ['java/util/Map$Entry', 'java/lang/String'] | ['java.util.Map$Entry', 'java.lang.String'] | Failed |
| name and type | ['length1:()I'] | ['length1:()I'] | Passed |
| index zero is invalid | [['bad-ref', 0]] | [['bad-ref', 0]] | Passed |
SHA-256 / 6512c2b1315b0d4fc6cb3509f30db58b2df7cccc9c215b176e997681b5fd9428
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(pool, queries):
table = {}
idx = 1
for e in pool:
table[idx] = e
idx += 2 if e[0] in ('Long', 'Double') else 1
def utf(i):
e = table.get(i)
if e is None or e[0] != 'Utf8':
raise LookupError(i)
return e[1]
def res(i):
e = table.get(i)
if e is None:
raise LookupError(i)
kind = e[0]
if kind == 'Utf8':
return e[1]
if kind in ('Integer', 'Long', 'Double'):
return e[1]
if kind == 'String':
return '"' + utf(e[1]) + '"'
if kind == 'Class':
return utf(e[1]).replace('/', '.', 1)
if kind == 'NameAndType':
return utf(e[1]) + ':' + utf(e[2])
if kind in ('Methodref', 'Fieldref'):
c = table.get(e[1])
if c is None or c[0] != 'Class':
raise LookupError(e[1])
n = table.get(e[2])
if n is None or n[0] != 'NameAndType':
raise LookupError(e[2])
return res(e[1]) + '.' + res(e[2])
raise LookupError(i)
out = []
for q in queries:
try:
out.append(res(q))
except LookupError as err:
out.append(['bad-ref', err.args[0]])
return out
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('regression: method reference',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[6]),
['java.lang.String.length1:()I']),
('entries after a Long keep their index',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[9, 8]),
[41, ['bad-ref', 8]]),
('entries after a Double keep their index',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[12, 18]),
['"length1"', 7]),
('field reference',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[13]),
['java.lang.String.length1:()I']),
('method reference with non-Class owner',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[14]),
[['bad-ref', 1]]),
('string constant pointing at an Integer',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[15]),
[['bad-ref', 9]]),
('nested package class name',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[17, 2]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[5]),
['length1:()I']),
('index zero is invalid',
([['Utf8', 'java/lang/String'],
['Class', 1],
['Utf8', 'length1'],
['Utf8', '()I'],
['NameAndType', 3, 4],
['Methodref', 2, 5],
['Long', 1234567890124],
['Integer', 41],
['Double', 2.5],
['String', 3],
['Fieldref', 2, 5],
['Methodref', 1, 5],
['String', 9],
['Utf8', 'java/util/Map$Entry'],
['Class', 16],
['Integer', 7]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[7]),
['java.lang.String.length2:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[10, 9]),
[42, ['bad-ref', 9]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[13, 19]),
['"length2"', 14]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[14]),
['java.lang.String.length2:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[15]),
[['bad-ref', 2]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[16]),
[['bad-ref', 10]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[18, 3]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[6]),
['length2:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'java/lang/String'],
['Class', 2],
['Utf8', 'length2'],
['Utf8', '()I'],
['NameAndType', 4, 5],
['Methodref', 3, 6],
['Long', 1234567890125],
['Integer', 42],
['Double', 5.0],
['String', 4],
['Fieldref', 3, 6],
['Methodref', 2, 6],
['String', 10],
['Utf8', 'java/util/Map$Entry'],
['Class', 17],
['Integer', 14]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[8]),
['java.lang.String.length3:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[11, 10]),
[43, ['bad-ref', 10]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[14, 20]),
['"length3"', 21]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[15]),
['java.lang.String.length3:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[16]),
[['bad-ref', 3]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[17]),
[['bad-ref', 11]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[19, 4]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[7]),
['length3:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'java/lang/String'],
['Class', 3],
['Utf8', 'length3'],
['Utf8', '()I'],
['NameAndType', 5, 6],
['Methodref', 4, 7],
['Long', 1234567890126],
['Integer', 43],
['Double', 7.5],
['String', 5],
['Fieldref', 4, 7],
['Methodref', 3, 7],
['String', 11],
['Utf8', 'java/util/Map$Entry'],
['Class', 18],
['Integer', 21]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[9]),
['java.lang.String.length4:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[12, 11]),
[44, ['bad-ref', 11]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[15, 21]),
['"length4"', 28]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[16]),
['java.lang.String.length4:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[17]),
[['bad-ref', 4]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[18]),
[['bad-ref', 12]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[20, 5]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[8]),
['length4:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'java/lang/String'],
['Class', 4],
['Utf8', 'length4'],
['Utf8', '()I'],
['NameAndType', 6, 7],
['Methodref', 5, 8],
['Long', 1234567890127],
['Integer', 44],
['Double', 10.0],
['String', 6],
['Fieldref', 5, 8],
['Methodref', 4, 8],
['String', 12],
['Utf8', 'java/util/Map$Entry'],
['Class', 19],
['Integer', 28]],
[0]),
[['bad-ref', 0]])],
[('regression: method reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[10]),
['java.lang.String.length5:()I']),
('entries after a Long keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[13, 12]),
[45, ['bad-ref', 12]]),
('entries after a Double keep their index',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[16, 22]),
['"length5"', 35]),
('field reference',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[17]),
['java.lang.String.length5:()I']),
('method reference with non-Class owner',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[18]),
[['bad-ref', 5]]),
('string constant pointing at an Integer',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[19]),
[['bad-ref', 13]]),
('nested package class name',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[21, 6]),
['java.util.Map$Entry', 'java.lang.String']),
('name and type',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[9]),
['length5:()I']),
('index zero is invalid',
([['Utf8', 'pad0'],
['Utf8', 'pad1'],
['Utf8', 'pad2'],
['Utf8', 'pad3'],
['Utf8', 'java/lang/String'],
['Class', 5],
['Utf8', 'length5'],
['Utf8', '()I'],
['NameAndType', 7, 8],
['Methodref', 6, 9],
['Long', 1234567890128],
['Integer', 45],
['Double', 12.5],
['String', 7],
['Fieldref', 6, 9],
['Methodref', 5, 9],
['String', 13],
['Utf8', 'java/util/Map$Entry'],
['Class', 20],
['Integer', 35]],
[0]),
[['bad-ref', 0]])]]
for label, args, expected in cases[N - 1]:
check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
| Boundary fixture | Actual | Expected | Outcome |
|---|---|---|---|
| regression: method reference | ['java.lang/String.length1:()I'] | ['java.lang.String.length1:()I'] | Failed |
| entries after a Long keep their index | [41, ['bad-ref', 8]] | [41, ['bad-ref', 8]] | Passed |
| entries after a Double keep their index | ['"length1"', 7] | ['"length1"', 7] | Passed |
| field reference | ['java.lang/String.length1:()I'] | ['java.lang.String.length1:()I'] | Failed |
| method reference with non-Class owner | [['bad-ref', 1]] | [['bad-ref', 1]] | Passed |
| string constant pointing at an Integer | [['bad-ref', 9]] | [['bad-ref', 9]] | Passed |
| nested package class name | ['java.util/Map$Entry', 'java.lang/String'] | ['java.util.Map$Entry', 'java.lang.String'] | Failed |
| name and type | ['length1:()I'] | ['length1:()I'] | Passed |
| index zero is invalid | [['bad-ref', 0]] | [['bad-ref', 0]] | Passed |
SHA-256 / d91042a0cd66ee714deeea77bd55a668b32e76e08320163f3fca9c5d9e5e506d
HELD IN THE MEMBER ARCHIVE
The verified repair and its recorded checks are member-only.
This mechanism has 9 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.
Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.
Member access is invitation-based. Sign in with your invited account to inspect the repair.
Sign in to the archive ↗Verification & scope
A deterministic, bounded teaching model of one bytecode virtual machine mechanism with a stipulated instruction encoding; it is not a production VM and claims no conformance to any real specification. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.
Observations recorded using Python 3.12.14 at 2026-09-29T14:51:23.109464+00:00.
Case digest / ae5d1fe3c998649c3b3fbadae5d792cc9f8b806f7f6b617adc30871829de1a47