jdk/src/java.base/share/classes/java/lang/constant/ConstantUtils.java
2023-05-23 21:26:25 +00:00

307 lines
12 KiB
Java

/*
* Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.lang.constant;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import static java.util.Objects.requireNonNull;
/**
* Helper methods for the implementation of {@code java.lang.constant}.
*/
class ConstantUtils {
/** an empty constant descriptor */
public static final ConstantDesc[] EMPTY_CONSTANTDESC = new ConstantDesc[0];
static final ClassDesc[] EMPTY_CLASSDESC = new ClassDesc[0];
static final Constable[] EMPTY_CONSTABLE = new Constable[0];
static final int MAX_ARRAY_TYPE_DESC_DIMENSIONS = 255;
private static final Set<String> pointyNames = Set.of(ConstantDescs.INIT_NAME, ConstantDescs.CLASS_INIT_NAME);
/**
* Validates the correctness of a binary class name. In particular checks for the presence of
* invalid characters in the name.
*
* @param name the class name
* @return the class name passed if valid
* @throws IllegalArgumentException if the class name is invalid
*/
static String validateBinaryClassName(String name) {
for (int i=0; i<name.length(); i++) {
char ch = name.charAt(i);
if (ch == ';' || ch == '[' || ch == '/')
throw new IllegalArgumentException("Invalid class name: " + name);
}
return name;
}
/**
* Validates the correctness of an internal class name.
* In particular checks for the presence of invalid characters in the name.
*
* @param name the class name
* @return the class name passed if valid
* @throws IllegalArgumentException if the class name is invalid
*/
static String validateInternalClassName(String name) {
for (int i=0; i<name.length(); i++) {
char ch = name.charAt(i);
if (ch == ';' || ch == '[' || ch == '.')
throw new IllegalArgumentException("Invalid class name: " + name);
}
return name;
}
/**
* Validates the correctness of a binary package name.
* In particular checks for the presence of invalid characters in the name.
* Empty package name is allowed.
*
* @param name the package name
* @return the package name passed if valid
* @throws IllegalArgumentException if the package name is invalid
* @throws NullPointerException if the package name is {@code null}
*/
public static String validateBinaryPackageName(String name) {
for (int i=0; i<name.length(); i++) {
char ch = name.charAt(i);
if (ch == ';' || ch == '[' || ch == '/')
throw new IllegalArgumentException("Invalid package name: " + name);
}
return name;
}
/**
* Validates the correctness of an internal package name.
* In particular checks for the presence of invalid characters in the name.
* Empty package name is allowed.
*
* @param name the package name
* @return the package name passed if valid
* @throws IllegalArgumentException if the package name is invalid
* @throws NullPointerException if the package name is {@code null}
*/
public static String validateInternalPackageName(String name) {
for (int i=0; i<name.length(); i++) {
char ch = name.charAt(i);
if (ch == ';' || ch == '[' || ch == '.')
throw new IllegalArgumentException("Invalid package name: " + name);
}
return name;
}
/**
* Validates the correctness of a module name.
* In particular checks for the presence of invalid characters in the name.
* Empty module name is allowed.
*
* {@jvms 4.2.3} Module and Package Names
*
* @param name the module name
* @return the module name passed if valid
* @throws IllegalArgumentException if the module name is invalid
* @throws NullPointerException if the module name is {@code null}
*/
public static String validateModuleName(String name) {
for (int i=name.length() - 1; i >= 0; i--) {
char ch = name.charAt(i);
if ((ch >= '\u0000' && ch <= '\u001F')
|| ((ch == '\\' || ch == ':' || ch =='@') && (i == 0 || name.charAt(--i) != '\\')))
throw new IllegalArgumentException("Invalid module name: " + name);
}
return name;
}
/**
* Validates a member name
*
* @param name the name of the member
* @return the name passed if valid
* @throws IllegalArgumentException if the member name is invalid
*/
public static String validateMemberName(String name, boolean method) {
requireNonNull(name);
if (name.length() == 0)
throw new IllegalArgumentException("zero-length member name");
for (int i=0; i<name.length(); i++) {
char ch = name.charAt(i);
if (ch == '.' || ch == ';' || ch == '[' || ch == '/')
throw new IllegalArgumentException("Invalid member name: " + name);
if (method && (ch == '<' || ch == '>')) {
if (!pointyNames.contains(name))
throw new IllegalArgumentException("Invalid member name: " + name);
}
}
return name;
}
static void validateClassOrInterface(ClassDesc classDesc) {
if (!classDesc.isClassOrInterface())
throw new IllegalArgumentException("not a class or interface type: " + classDesc);
}
static int arrayDepth(String descriptorString) {
int depth = 0;
while (descriptorString.charAt(depth) == '[')
depth++;
return depth;
}
static String binaryToInternal(String name) {
return name.replace('.', '/');
}
static String internalToBinary(String name) {
return name.replace('/', '.');
}
static String dropLastChar(String s) {
return s.substring(0, s.length() - 1);
}
static String dropFirstAndLastChar(String s) {
return s.substring(1, s.length() - 1);
}
/**
* Parses a method descriptor string, and return a list of field descriptor
* strings, return type first, then parameter types
*
* @param descriptor the descriptor string
* @return the list of types
* @throws IllegalArgumentException if the descriptor string is not valid
*/
static List<String> parseMethodDescriptor(String descriptor) {
int cur = 0, end = descriptor.length();
ArrayList<String> ptypes = new ArrayList<>();
ptypes.add(null); //placeholder for return type
if (cur >= end || descriptor.charAt(cur) != '(')
throw new IllegalArgumentException("Bad method descriptor: " + descriptor);
++cur; // skip '('
while (cur < end && descriptor.charAt(cur) != ')') {
int len = skipOverFieldSignature(descriptor, cur, end, false);
if (len == 0)
throw new IllegalArgumentException("Bad method descriptor: " + descriptor);
ptypes.add(descriptor.substring(cur, cur + len));
cur += len;
}
if (cur >= end)
throw new IllegalArgumentException("Bad method descriptor: " + descriptor);
++cur; // skip ')'
int rLen = skipOverFieldSignature(descriptor, cur, end, true);
if (rLen == 0 || cur + rLen != end)
throw new IllegalArgumentException("Bad method descriptor: " + descriptor);
ptypes.set(0, descriptor.substring(cur, cur + rLen));
return ptypes;
}
private static final char JVM_SIGNATURE_ARRAY = '[';
private static final char JVM_SIGNATURE_BYTE = 'B';
private static final char JVM_SIGNATURE_CHAR = 'C';
private static final char JVM_SIGNATURE_CLASS = 'L';
private static final char JVM_SIGNATURE_ENDCLASS = ';';
private static final char JVM_SIGNATURE_ENUM = 'E';
private static final char JVM_SIGNATURE_FLOAT = 'F';
private static final char JVM_SIGNATURE_DOUBLE = 'D';
private static final char JVM_SIGNATURE_FUNC = '(';
private static final char JVM_SIGNATURE_ENDFUNC = ')';
private static final char JVM_SIGNATURE_INT = 'I';
private static final char JVM_SIGNATURE_LONG = 'J';
private static final char JVM_SIGNATURE_SHORT = 'S';
private static final char JVM_SIGNATURE_VOID = 'V';
private static final char JVM_SIGNATURE_BOOLEAN = 'Z';
/**
* Validates that the characters at [start, end) within the provided string
* describe a valid field type descriptor.
* @param descriptor the descriptor string
* @param start the starting index into the string
* @param end the ending index within the string
* @param voidOK is void acceptable?
* @return the length of the descriptor, or 0 if it is not a descriptor
* @throws IllegalArgumentException if the descriptor string is not valid
*/
@SuppressWarnings("fallthrough")
static int skipOverFieldSignature(String descriptor, int start, int end, boolean voidOK) {
int arrayDim = 0;
int index = start;
while (index < end) {
switch (descriptor.charAt(index)) {
case JVM_SIGNATURE_VOID: if (!voidOK) { return 0; }
case JVM_SIGNATURE_BOOLEAN:
case JVM_SIGNATURE_BYTE:
case JVM_SIGNATURE_CHAR:
case JVM_SIGNATURE_SHORT:
case JVM_SIGNATURE_INT:
case JVM_SIGNATURE_FLOAT:
case JVM_SIGNATURE_LONG:
case JVM_SIGNATURE_DOUBLE:
return index - start + 1;
case JVM_SIGNATURE_CLASS:
// state variable for detection of illegal states, such as:
// empty unqualified name, '//', leading '/', or trailing '/'
boolean legal = false;
while (++index < end) {
switch (descriptor.charAt(index)) {
case ';' -> {
// illegal state on parser exit indicates empty unqualified name or trailing '/'
return legal ? index - start + 1 : 0;
}
case '.', '[' -> {
// do not permit '.' or '['
return 0;
}
case '/' -> {
// illegal state when received '/' indicates '//' or leading '/'
if (!legal) return 0;
legal = false;
}
default ->
legal = true;
}
}
return 0;
case JVM_SIGNATURE_ARRAY:
arrayDim++;
if (arrayDim > MAX_ARRAY_TYPE_DESC_DIMENSIONS) {
throw new IllegalArgumentException(String.format("Cannot create an array type descriptor with more than %d dimensions",
ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS));
}
// The rest of what's there better be a legal descriptor
index++;
voidOK = false;
break;
default:
return 0;
}
}
return 0;
}
}