[Refactor] Add InputSupplier API for supporting different way of inputs.

src/main/java/net/fabricmc/tinyremapper/ClassInstance.java

@@ -18,7 +18,6 @@
 
 package net.fabricmc.tinyremapper;
 
-import java.nio.file.Path;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -51,12 +50,12 @@
 import net.fabricmc.tinyremapper.api.TrMethod;
 
 public final class ClassInstance implements TrClass {
-	ClassInstance(TinyRemapper tr, boolean isInput, InputTag[] inputTags, Path srcFile, byte[] data) {
+	ClassInstance(TinyRemapper tr, boolean isInput, InputTag[] inputTags, String source, byte[] data) {
 		assert !isInput || data != null;
 		this.tr = tr;
 		this.isInput = isInput;
 		this.inputTags = inputTags;
-		this.srcPath = srcFile;
+		this.source = source;
 		this.data = data;
 		this.mrjOrigin = this;
 	}
@@ -837,7 +836,7 @@ private static <T extends TrMember> void addMatching(T member, String name, Stri
 
 	ClassInstance constructMrjCopy(MrjState newContext) {
 		// isInput should be false, since the MRJ copy should not be emitted
-		ClassInstance copy = new ClassInstance(tr, false, inputTags, srcPath, data);
+		ClassInstance copy = new ClassInstance(tr, false, inputTags, source, data);
 		copy.init(mrjVersion, name, signature, superName, access, interfaces);
 		copy.setContext(newContext);
 
@@ -870,6 +869,10 @@ public static String getMrjName(String clsName, int mrjVersion) {
 		}
 	}
 
+	/**
+	 * @deprecated Please use {@link TrEnvironment#DEFAULT_MRJ_VERSION}.
+	 */
+	@Deprecated
 	public static final int MRJ_DEFAULT = -1;
 	public static final String MRJ_PREFIX = "/META-INF/versions";
 
@@ -882,7 +885,7 @@ public static String getMrjName(String clsName, int mrjVersion) {
 
 	final boolean isInput;
 	private volatile InputTag[] inputTags; // cow input tag list, null for none
-	final Path srcPath;
+	final String source;
 	byte[] data;
 	private ClassInstance mrjOrigin;
 	private final Map<String, MemberInstance> members = new HashMap<>(); // methods and fields are distinct due to their different desc separators

src/main/java/net/fabricmc/tinyremapper/FileSystemHandler.java

@@ -20,10 +20,12 @@
 
 import java.io.IOException;
 import java.net.URI;
+import java.net.URISyntaxException;
 import java.nio.file.FileSystem;
 import java.nio.file.FileSystemAlreadyExistsException;
 import java.nio.file.FileSystemNotFoundException;
 import java.nio.file.FileSystems;
+import java.nio.file.Path;
 import java.util.Collections;
 import java.util.IdentityHashMap;
 import java.util.Map;
@@ -36,6 +38,14 @@
  * invocations are mirrored.
  */
 public final class FileSystemHandler {
+	public static synchronized FileSystem open(Path path) throws IOException {
+		try {
+			return open(new URI("jar:" + path.toUri()));
+		} catch (URISyntaxException e) {
+			throw new RuntimeException(e);
+		}
+	}
+
 	public static synchronized FileSystem open(URI uri) throws IOException {
 		boolean opened = false;
 		FileSystem ret = null;