Add support for automatically rewriting array types in the rewriter

This adds a new rewriteUnwrappedType to the TypeRewriter class, which
gets called with the unwrapped type for array types, with the potentially
modified return value automatically being re-array-ified.

dexlib2/src/main/java/org/jf/dexlib2/rewriter/TypeRewriter.java

@@ -35,6 +35,29 @@ import javax.annotation.Nonnull;
 
 public class TypeRewriter implements Rewriter<String> {
     @Nonnull @Override public String rewrite(@Nonnull String value) {
+        if (value.length() > 0 && value.charAt(0) == '[') {
+            int dimensions = value.lastIndexOf("[") + 1;
+
+            String arraySpecifiers = value.substring(0, dimensions);
+            String unwrappedType = value.substring(dimensions);
+            String rewrittenType = rewriteUnwrappedType(unwrappedType);
+            return arraySpecifiers + rewrittenType;
+        } else {
+            return rewriteUnwrappedType(value);
+        }
+    }
+
+    /**
+     * This is called by the default rewrite implementation with the unwrapped type.
+     *
+     * <p>For array types, the unwrapped type is the type with the array specifiers removed. And there is no difference
+     * for non-array types.
+     *
+     * @param value The unwrapped type
+     * @return The modified version of the unwrapped type. This will be re-array-ified if the original wrapped type was
+     * an array.
+     */
+    @Nonnull public String rewriteUnwrappedType(@Nonnull String value) {
         return value;
     }
 }

dexlib2/src/test/java/org/jf/dexlib2/rewriter/RewriteArrayTypeTest.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2020, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.jf.dexlib2.rewriter;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Lists;
+import org.jf.dexlib2.AccessFlags;
+import org.jf.dexlib2.AnnotationVisibility;
+import org.jf.dexlib2.Opcodes;
+import org.jf.dexlib2.iface.*;
+import org.jf.dexlib2.immutable.*;
+import org.junit.Assert;
+import org.junit.Test;
+
+import javax.annotation.Nonnull;
+
+public class RewriteArrayTypeTest {
+    @Test
+    public void testRewriteArrayTypeTest() {
+        ClassDef class1 = new ImmutableClassDef("Lcls1;", AccessFlags.PUBLIC.getValue(), "Ljava/lang/Object;", null, null,
+                Lists.newArrayList(new ImmutableAnnotation(AnnotationVisibility.RUNTIME, "Lannotation;", null)),
+                Lists.<Field>newArrayList(
+                        new ImmutableField("Lcls1;", "field1", "I", AccessFlags.PUBLIC.getValue(), null, null, null)
+                ),
+                Lists.<Method>newArrayList(
+                        new ImmutableMethod("Lcls1", "method1",
+                                Lists.<MethodParameter>newArrayList(new ImmutableMethodParameter("[[[Lcls1;", null, null)), "V",
+                                AccessFlags.PUBLIC.getValue(), null, null, null)));
+
+        ImmutableDexFile dexFile = new ImmutableDexFile(Opcodes.getDefault(), ImmutableSet.of(class1));
+
+
+        DexRewriter rewriter = new DexRewriter(new RewriterModule() {
+            @Nonnull @Override public Rewriter<String> getTypeRewriter(@Nonnull Rewriters rewriters) {
+                return new TypeRewriter() {
+                    @Nonnull @Override public String rewriteUnwrappedType(@Nonnull String value) {
+                        if (value.equals("Lcls1;")) {
+                            return "Lcls2;";
+                        }
+                        return value;
+                    }
+                };
+            }
+        });
+
+        DexFile rewrittenDexFile = rewriter.rewriteDexFile(dexFile);
+
+        ClassDef rewrittenClassDef = Lists.newArrayList(rewrittenDexFile.getClasses()).get(0);
+        Method rewrittenMethodDef = Lists.newArrayList(rewrittenClassDef.getMethods()).get(0);
+
+        Assert.assertEquals(rewrittenClassDef.getType(), "Lcls2;");
+        Assert.assertEquals(rewrittenMethodDef.getParameterTypes().get(0), "[[[Lcls2;");
+    }
+}