1 files changed, 121 insertions, 0 deletions
diff --git a/dx/src/com/android/dx/io/CodeReader.java b/dx/src/com/android/dx/io/CodeReader.java
new file mode 100644
index 0000000..cab1063
--- /dev/null
+++ b/dx/src/com/android/dx/io/CodeReader.java
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.dx.io;
+
+import com.android.dx.io.instructions.DecodedInstruction;
+import com.android.dx.util.DexException;
+
+/**
+ * Walks through a block of code and calls visitor call backs.
+ */
+public final class CodeReader {
+    private Visitor fallbackVisitor = null;
+    private Visitor stringVisitor = null;
+    private Visitor typeVisitor = null;
+    private Visitor fieldVisitor = null;
+    private Visitor methodVisitor = null;
+
+    /**
+     * Sets {@code visitor} as the visitor for all instructions.
+     */
+    public void setAllVisitors(Visitor visitor) {
+        fallbackVisitor = visitor;
+        stringVisitor = visitor;
+        typeVisitor = visitor;
+        fieldVisitor = visitor;
+        methodVisitor = visitor;
+    }
+
+    /**
+     * Sets {@code visitor} as the visitor for all instructions not
+     * otherwise handled.
+     */
+    public void setFallbackVisitor(Visitor visitor) {
+        fallbackVisitor = visitor;
+    }
+
+    /**
+     * Sets {@code visitor} as the visitor for all string instructions.
+     */
+    public void setStringVisitor(Visitor visitor) {
+        stringVisitor = visitor;
+    }
+
+    /**
+     * Sets {@code visitor} as the visitor for all type instructions.
+     */
+    public void setTypeVisitor(Visitor visitor) {
+        typeVisitor = visitor;
+    }
+
+    /**
+     * Sets {@code visitor} as the visitor for all field instructions.
+     */
+    public void setFieldVisitor(Visitor visitor) {
+        fieldVisitor = visitor;
+    }
+
+    /**
+     * Sets {@code visitor} as the visitor for all method instructions.
+     */
+    public void setMethodVisitor(Visitor visitor) {
+        methodVisitor = visitor;
+    }
+
+    public void visitAll(DecodedInstruction[] decodedInstructions)
+            throws DexException {
+        int size = decodedInstructions.length;
+
+        for (int i = 0; i < size; i++) {
+            DecodedInstruction one = decodedInstructions[i];
+            if (one == null) {
+                continue;
+            }
+
+            callVisit(decodedInstructions, one);
+        }
+    }
+
+    public void visitAll(short[] encodedInstructions) throws DexException {
+        DecodedInstruction[] decodedInstructions =
+            DecodedInstruction.decodeAll(encodedInstructions);
+        visitAll(decodedInstructions);
+    }
+
+    private void callVisit(DecodedInstruction[] all, DecodedInstruction one) {
+        Visitor visitor = null;
+
+        switch (OpcodeInfo.getIndexType(one.getOpcode())) {
+            case STRING_REF: visitor = stringVisitor; break;
+            case TYPE_REF:   visitor = typeVisitor;   break;
+            case FIELD_REF:  visitor = fieldVisitor;  break;
+            case METHOD_REF: visitor = methodVisitor; break;
+        }
+
+        if (visitor == null) {
+            visitor = fallbackVisitor;
+        }
+
+        if (visitor != null) {
+            visitor.visit(all, one);
+        }
+    }
+
+    public interface Visitor {
+        void visit(DecodedInstruction[] all, DecodedInstruction one);
+    }
+}