我们正在迁移旧代码,实际上对于 Java 11 来说已经很旧了。我在编译其中一个类时遇到了问题。示例代码为:
package XXXX;
import java.lang.ref.*;
import sun.security.action.*;
import java.security.*;
import java.io.*;
class Converters
{
private static Object lock;
private static String converterPackageName;
private static String defaultEncoding;
public static final int BYTE_TO_CHAR = 0;
public static final int CHAR_TO_BYTE = 1;
private static final String[] converterPrefix;
private static SoftReference[] classCache;
static /* synthetic */ Class class$sun$io$Converters;
private static String getConverterPackageName() {
final String converterPackageName = Converters.converterPackageName;
if (converterPackageName != null) {
return converterPackageName;
}
String converterPackageName2 = AccessController.doPrivileged((PrivilegedAction<String>)new GetPropertyAction("file.encoding.pkg"));
if (converterPackageName2 != null) {
Converters.converterPackageName = converterPackageName2;
}
else {
converterPackageName2 = "sun.io";
}
return converterPackageName2;
}
private static Class getConverterClass(final int n, final String s) throws UnsupportedEncodingException {
String aliasName = null;
if (!s.equals("ISO8859_1")) {
if (s.equals("8859_1")) {
aliasName = "ISO8859_1";
}
else if (s.equals("ISO8859-1")) {
aliasName = "ISO8859_1";
}
else if (s.equals("646")) {
aliasName = "ASCII";
}
else {
aliasName = CharacterEncoding.aliasName(s);
}
}
if (aliasName == null) {
aliasName = s;
}
try {
return Class.forName(getConverterPackageName() + "." + Converters.converterPrefix[n] + aliasName);
}
catch (ClassNotFoundException ex) {
throw new UnsupportedEncodingException(aliasName);
}
}
private static Object newConverter(final String s, final Class clazz) throws UnsupportedEncodingException {
try {
return clazz.newInstance();
}
catch (InstantiationException ex) {
throw new UnsupportedEncodingException(s);
}
catch (IllegalAccessException ex2) {
throw new UnsupportedEncodingException(s);
}
}
static Object newConverter(final int n, final String s) throws UnsupportedEncodingException {
final Class converterClass;
synchronized (Converters.lock) {
converterClass = getConverterClass(n, s);
}
return newConverter(s, converterClass);
}
private static Class getDefaultConverterClass(final int n) {
boolean b = false;
final SoftReference softReference = Converters.classCache[n];
if (softReference != null) {
final Class clazz = softReference.get();
if (clazz != null) {
return clazz;
}
Converters.classCache[n] = null;
}
String defaultEncoding = Converters.defaultEncoding;
if (Converters.defaultEncoding != null) {
b = true;
}
else {
defaultEncoding = AccessController.doPrivileged((PrivilegedAction<String>)new GetPropertyAction("file.encoding"));
if (defaultEncoding != null) {
Converters.defaultEncoding = defaultEncoding;
b = true;
}
else {
defaultEncoding = "ISO8859_1";
}
}
Class clazz2;
try {
clazz2 = getConverterClass(n, defaultEncoding);
if (b) {
Converters.classCache[n] = new SoftReference(clazz2);
}
}
catch (UnsupportedEncodingException ex) {
try {
clazz2 = getConverterClass(n, "ISO8859_1");
}
catch (UnsupportedEncodingException ex2) {
throw new InternalError("Cannot find default " + Converters.converterPrefix[n] + " converter class");
}
}
return clazz2;
}
static Object newDefaultConverter(final int n) {
final Class defaultConverterClass;
synchronized (Converters.lock) {
defaultConverterClass = getDefaultConverterClass(n);
}
try {
return newConverter("", defaultConverterClass);
}
catch (UnsupportedEncodingException ex) {
throw new InternalError("Cannot instantiate default converter class " + defaultConverterClass.getName());
}
}
static /* synthetic */ Class class$(final String s) {
try {
return Class.forName(s);
}
catch (ClassNotFoundException ex) {
throw new NoClassDefFoundError(ex.getMessage());
}
}
static {
Converters.lock = ((Converters.class$sun$io$Converters == null) ? (Converters.class$sun$io$Converters = class$("sun.io.Converters")) : Converters.class$sun$io$Converters);
Converters.converterPackageName = null;
Converters.defaultEncoding = null;
converterPrefix = new String[] { "ByteToChar", "CharToByte" };
Converters.classCache = new SoftReference[2];
}
}
使用
javac Converter.java
编译它时,我收到以下错误:
import sun.security.action.*;
^
(package sun.security.action is declared in module java.base, which does not export it to the unnamed module)
Converters.java:47: error: cannot find symbol
aliasName = CharacterEncoding.aliasName(s);
^
symbol: variable CharacterEncoding
location: class Converters
Converters.java:85: error: incompatible types: Object cannot be converted to Class
final Class clazz = softReference.get();
^
Note: Converters.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: Converters.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
3 errors
我尝试使用
--add--export
java.base/sun.security=All-UNNAMED
导出它,它仍然抛出错误。
有什么帮助吗?我还想知道是否有其他方法可以用新代码删除旧的遗留代码。
从 Java 9 开始,大多数 JDK 的内部 API 在编译时都无法访问(并且将来,它们在运行时也将无法访问)。 sun.security.action
是一个内部包,所以你应该避免使用它。在你的情况下,你可以简单地删除
new GetPropertyAction("file.encoding.pkg")
并用 lambda 替换它:
AccessController.doPrivileged((PrivilegedAction<Object>) () -> System.getProperty("prop"));
--add-export
,这应该可行!你的
--add-export
论点是错误的。您需要使用正确的包来导出(在您的情况下是
sun.security.action
)和模块的名称(如果您不使用模块,则全部未命名,全部以大写字母!)。 所以这应该是
--add-exports java.base/sun.security.action=ALL-UNNAMED
--add-exports module/package=other-module(,other-module)* 指定一个包被视为从其定义模块导出到 附加模块或所有未命名模块,当值 其他模块全部未命名。
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>ru.readcrl_2</groupId>
<artifactId>ReadCRL_2</artifactId>
<version>2.0-SNAPSHOT</version>
<packaging>jar</packaging>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.11.0</version>
<configuration>
<showDeprecation>true</showDeprecation>
<compilerArgs>
<arg>--add-exports</arg>
<arg>java.base/sun.security.x509=ALL-UNNAMED</arg>
</compilerArgs>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>org.bouncycastle</groupId>
<artifactId>bcpkix-jdk15on</artifactId>
<version>1.70</version>
</dependency>
<dependency>
<groupId>org.bouncycastle</groupId>
<artifactId>bcprov-jdk15on</artifactId>
<version>1.70</version>
<type>jar</type>
</dependency>
</dependencies>
<reporting>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
<configuration>
<configLocation>config/sun_checks.xml</configLocation>
</configuration>
</plugin>
</plugins>
</reporting>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>17</maven.compiler.source>
<maven.compiler.target>17</maven.compiler.target>
</properties>
</project>