#752: Add getKeys to JSch which makes access to all the config values…

src/main/java/com/jcraft/jsch/JSch.java

@@ -27,8 +27,11 @@
 package com.jcraft.jsch;
 
 import java.io.InputStream;
+import java.util.Collections;
 import java.util.Enumeration;
+import java.util.HashMap;
 import java.util.Hashtable;
+import java.util.Map;
 import java.util.Vector;
 
 public class JSch {
@@ -639,6 +642,23 @@ public static void setConfig(String key, String value) {
     }
   }
 
+  /**
+   * Gets the configuration
+   */
+  public static Map<String, String> getConfig() {
+    Map<String, String> ret = new HashMap<>();
+    synchronized (config) {
+      for (Map.Entry<String, String> entry : config.entrySet()) {
+        String key = entry.getKey();
+        if (key.equals("PubkeyAcceptedKeyTypes")) {
+          key = "PubkeyAcceptedAlgorithms";
+        }
+        ret.put(key, entry.getValue());
+      }
+    }
+    return Collections.unmodifiableMap(ret);
+  }
+
   /**
    * Sets the logger
    *

src/test/java/com/jcraft/jsch/JSchTest.java

@@ -2,8 +2,11 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.util.Hashtable;
+import java.util.Map;
+
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -64,6 +67,26 @@ void checkLoggerBehavior() throws Exception {
     assertSame(JSch.DEVNULL, jsch.getInstanceLogger(), "instance logger should be DEVNULL");
   }
 
+  @Test
+  void getConfig() {
+    Map<String, String> map = JSch.getConfig();
+
+    // there are many keys so just assert a high number in case new keys
+    // are added so this test still passes
+    int before = map.size();
+    assertTrue(before > 150);
+    assertTrue(map.containsKey("diffie-hellman-group14-sha256"));
+    assertTrue(map.containsKey("HashKnownHosts"));
+
+    // add new key
+    JSch.setConfig("mySpecialKey", "mySpecialValue");
+
+    // add 1 new key
+    map = JSch.getConfig();
+    int after = map.size();
+    assertEquals(before + 1, after);
+  }
+
   static final class TestLogger implements Logger {
     @Override
     public boolean isEnabled(int level) {