FileReader

downgradetest/src/main/java/xyz/wagyourtail/downgradetest/TestFile.java

@@ -17,7 +17,7 @@ public static void main(String[] args) throws IOException {
         writer2.write("Goodbye World!");
         writer2.close();
 
-        FileReader reader = new FileReader(new File("build/test/test.txt"), StandardCharsets.UTF_8);
+        FileReader reader = new FileReader("build/test/test.txt", StandardCharsets.UTF_8);
         StringBuilder sb = new StringBuilder();
         int c;
         while ((c = reader.read()) != -1) {

java-api/src/java11/java/xyz/wagyourtail/jvmdg/j11/stub/java_base/J_I_FileReader.java

@@ -1,32 +1,79 @@
 package xyz.wagyourtail.jvmdg.j11.stub.java_base;
 
 
-import xyz.wagyourtail.jvmdg.version.Adapter;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.InsnList;
+import org.objectweb.asm.tree.InsnNode;
+import org.objectweb.asm.tree.MethodInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+import xyz.wagyourtail.jvmdg.util.Utils;
+import xyz.wagyourtail.jvmdg.version.Modify;
+import xyz.wagyourtail.jvmdg.version.Ref;
 
 import java.io.*;
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
 import java.nio.charset.Charset;
+import java.nio.charset.CharsetDecoder;
+import java.nio.charset.CodingErrorAction;
 
-@Adapter("Ljava/io/FileReader;")
-public class J_I_FileReader extends InputStreamReader {
-
-    public J_I_FileReader(String fileName) throws FileNotFoundException {
-        super(new FileInputStream(fileName));
+public class J_I_FileReader {
+    private static final MethodHandles.Lookup IMPL_LOOKUP = Utils.getImplLookup();
+    private static final MethodHandle sdGetter;
+    private static final MethodHandle decSetter;
+    static {
+        MethodHandle seGet = null;
+        MethodHandle decSet = null;
+        try {
+            Class<?> sd = Class.forName("sun.nio.cs.StreamDecoder");
+            seGet = IMPL_LOOKUP.findGetter(FileReader.class, "sd", sd);
+            decSet = IMPL_LOOKUP.findSetter(sd, "decoder", CharsetDecoder.class);
+        } catch (Throwable t) {
+            t.printStackTrace();
+        }
+        sdGetter = seGet;
+        decSetter = decSet;
     }
 
-    public J_I_FileReader(File file) throws FileNotFoundException {
-        super(new FileInputStream(file));
+    public static void setCharset(FileReader fw, Charset charset) {
+        try {
+            Object sd = sdGetter.invoke(fw);
+            decSetter.invoke(sd, charset.newDecoder().onMalformedInput(CodingErrorAction.REPLACE).onUnmappableCharacter(CodingErrorAction.REPLACE));
+        } catch (Throwable t) {
+            Utils.sneakyThrow(t);
+        }
     }
 
-    public J_I_FileReader(FileDescriptor fd) {
-        super(new FileInputStream(fd));
-    }
+    @Modify(ref = @Ref(value = "java/io/FileReader", member = "<init>", desc = "(Ljava/lang/String;Ljava/nio/charset/Charset;)V"))
+    public static void init1(MethodNode mnode, int i) {
+        MethodInsnNode node = (MethodInsnNode) mnode.instructions.get(i);
+        Type firstArgType = Type.getArgumentTypes(node.desc)[0];
+        InsnList list = new InsnList();
+        // stack: (U) FileReader, String, Charset
+        list.add(new InsnNode(Opcodes.DUP_X2));
+        // stack: Charset, (U) FileReader, String, Charset
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: Charset, (U) FileReader, String
+        list.add(new InsnNode(Opcodes.DUP2));
+        // stack: Charset, (U) FileReader, String, (U) FileReader, String
+        // call init
+        list.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, "java/io/FileReader", "<init>", Type.getMethodDescriptor(Type.VOID_TYPE, firstArgType), false));
+        // stack: Charset, FileReader, String
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: Charset, FileReader
+        list.add(new InsnNode(Opcodes.SWAP));
+        // stack: FileReader, Charset
+        list.add(new MethodInsnNode(Opcodes.INVOKESTATIC, Type.getType(J_I_FileReader.class).getInternalName(), "setCharset", "(Ljava/io/FileReader;Ljava/nio/charset/Charset;)V", false));
 
-    public J_I_FileReader(String fileName, Charset charset) throws IOException {
-        super(new FileInputStream(fileName), charset);
+        mnode.instructions.insert(node, list);
+        mnode.instructions.remove(node);
     }
 
-    public J_I_FileReader(File file, Charset charset) throws IOException {
-        super(new FileInputStream(file), charset);
+
+    @Modify(ref = @Ref(value = "java/io/FileReader", member = "<init>", desc = "(Ljava/io/File;Ljava/nio/charset/Charset;)V"))
+    public static void init3(MethodNode mnode, int i) {
+        init1(mnode, i);
     }
 
 }

java-api/src/java11/java/xyz/wagyourtail/jvmdg/j11/stub/java_base/J_I_FileWriter.java

@@ -18,7 +18,6 @@
 import java.nio.charset.CharsetEncoder;
 import java.nio.charset.CodingErrorAction;
 
-//@Adapter("Ljava/io/FileWriter;")
 public class J_I_FileWriter {
     private static final MethodHandles.Lookup IMPL_LOOKUP = Utils.getImplLookup();
     private static final MethodHandle seGetter;
@@ -46,15 +45,6 @@ public static void setCharset(FileWriter fw, Charset charset) {
         }
     }
 
-//    public J_I_FileWriter(File file, Charset charset) throws IOException {
-//        super(new FileOutputStream(file), charset);
-//    }
-//
-//    public J_I_FileWriter(File file, Charset charset, boolean append) throws IOException {
-//        super(new FileOutputStream(file, append), charset);
-//    }
-
-
     @Modify(ref = @Ref(value = "java/io/FileWriter", member = "<init>", desc = "(Ljava/lang/String;Ljava/nio/charset/Charset;)V"))
     public static void init1(MethodNode mnode, int i) {
         MethodInsnNode node = (MethodInsnNode) mnode.instructions.get(i);