添加证书类型判断

src/main/java/com/sunyard/constant/CertUsage.java

@@ -0,0 +1,16 @@
+package com.sunyard.constant;
+
+/**
+ * 证书用途
+ */
+public enum CertUsage {
+    digitalSignature,
+    nonRepudiation,
+    keyEncipherment,
+    dataEncipherment,
+    keyAgreement,
+    keyCertSign,
+    cRLSign,
+    encipherOnly,
+    decipherOnly
+}