#54 step-2(add xdag evm interface)

src/main/java/io/xdag/core/TransactionType.java

@@ -0,0 +1,73 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020-2030 The XdagJ Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package io.xdag.core;
+
+public enum TransactionType {
+
+    /**
+     * (0x00) Coinbase transaction
+     */
+    COINBASE(0x00),
+
+    /**
+     * (0x01) Balance transfer.
+     */
+    TRANSFER(0x01),
+
+    /**
+     * (0x05) Create a contract.
+     */
+    CREATE(0x05),
+
+    /**
+     * (0x06) Call a contract.
+     */
+    CALL(0x06);
+
+    private static final TransactionType[] map = new TransactionType[256];
+    static {
+        for (TransactionType tt : TransactionType.values()) {
+            map[tt.code] = tt;
+        }
+    }
+
+    public static TransactionType of(byte code) {
+        return map[0xff & code];
+    }
+
+    private int code;
+
+    TransactionType(int code) {
+        this.code = code;
+    }
+
+    public int getCode() {
+        return code;
+    }
+
+    public byte toByte() {
+        return (byte) code;
+    }
+
+}