From 559cb7b8370a6a5359fe0bf3edeba649bad1be13 Mon Sep 17 00:00:00 2001
From: Thomas Scheffler <github@yagee.de>
Date: Tue, 19 Nov 2024 11:50:23 +0100
Subject: [PATCH] MCR-3224 activate PMD rule AvoidMessageDigestField

---
 .../datamodel/ifs/MCRContentInputStream.java    | 17 +++++++++--------
 ruleset.xml                                     |  3 ---
 2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/mycore-base/src/main/java/org/mycore/datamodel/ifs/MCRContentInputStream.java b/mycore-base/src/main/java/org/mycore/datamodel/ifs/MCRContentInputStream.java
index 292ba78e3b..16448bd60f 100644
--- a/mycore-base/src/main/java/org/mycore/datamodel/ifs/MCRContentInputStream.java
+++ b/mycore-base/src/main/java/org/mycore/datamodel/ifs/MCRContentInputStream.java
@@ -35,7 +35,7 @@
  * provides the header of the file that is read (the first 64k) for content type
  * detection purposes, counts the number of bytes read and builds an MD5
  * checksum String while content goes through this input stream.
- * 
+ *
  * @author Frank Lützenkirchen
  */
 public class MCRContentInputStream extends FilterInputStream {
@@ -46,6 +46,7 @@ public class MCRContentInputStream extends FilterInputStream {
     protected byte[] md5 = null;
 
     /** The message digest to build the MD5 checksum */
+    @SuppressWarnings("PMD.AvoidMessageDigestField") //InputStream is not thread safe either
     protected MessageDigest digest = null;
 
     /** The total number of bytes read so far */
@@ -56,7 +57,7 @@ public class MCRContentInputStream extends FilterInputStream {
 
     /**
      * Constructs a new MCRContentInputStream
-     * 
+     *
      * @param in
      *            the InputStream to read from
      * @throws MCRConfigurationException
@@ -138,7 +139,7 @@ public int read(byte[] buf, int off, int len) throws IOException {
     /**
      * Returns the first 64 k of the underlying input stream. This is used for
      * content type detection during file import into MyCoRe.
-     * 
+     *
      * @return the first 64 k of the input stream
      */
     public byte[] getHeader() {
@@ -147,7 +148,7 @@ public byte[] getHeader() {
 
     /**
      * Returns the number of bytes read so far
-     * 
+     *
      * @return the number of bytes read
      */
     public long getLength() {
@@ -157,7 +158,7 @@ public long getLength() {
     /**
      * Returns the MD5 message digest that has been built during reading of the
      * underlying input stream.
-     * 
+     *
      * @return the MD5 message digest checksum of all bytes that have been read
      */
     public byte[] getMD5() {
@@ -169,7 +170,7 @@ public byte[] getMD5() {
 
     /**
      * Returns the MD5 checksum as a String
-     * 
+     *
      * @return the MD5 checksum as a String of hex digits
      */
     public String getMD5String() {
@@ -178,7 +179,7 @@ public String getMD5String() {
 
     /**
      * Given an MD5 message digest, returns the MD5 checksum as a String
-     * 
+     *
      * @return the MD5 checksum as a String of hex digits
      */
     public static String getMD5String(byte[] digest) {
@@ -191,7 +192,7 @@ public static String getMD5String(byte[] digest) {
 
     /**
      * Builds a MessageDigest instance for MD5 checksum computation.
-     * 
+     *
      * @throws MCRConfigurationException
      *             if no java classes that support MD5 algorithm could be found
      */
diff --git a/ruleset.xml b/ruleset.xml
index d05d363fd6..e5fcfa2fd5 100644
--- a/ruleset.xml
+++ b/ruleset.xml
@@ -17,10 +17,7 @@
   <!-- Best Practices Rules -->
   <rule ref="category/java/bestpractices.xml/AbstractClassWithoutAbstractMethod"/>
   <rule ref="category/java/bestpractices.xml/ArrayIsStoredDirectly"/>
-  <!-- TODO: Create PR to fix this rule -->
-  <!--
   <rule ref="category/java/bestpractices.xml/AvoidMessageDigestField"/>
-  -->
   <rule ref="category/java/bestpractices.xml/AvoidPrintStackTrace"/>
   <rule ref="category/java/bestpractices.xml/AvoidReassigningCatchVariables"/>
   <!-- TODO: Create PR to fix this rule -->