diff --git a/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/pom.xml b/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/pom.xml
index 23fecff16f..d2cda0ade2 100644
--- a/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/pom.xml
+++ b/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/pom.xml
@@ -94,6 +94,10 @@
                     <groupId>org.opensaml</groupId>
                     <artifactId>xmltooling</artifactId>
                 </exclusion>
+                <exclusion>
+                    <groupId>jboss</groupId>
+                    <artifactId>javassist</artifactId>
+                </exclusion>
             </exclusions>
         </dependency>
         <dependency>
@@ -146,6 +150,16 @@
             <artifactId>h2-database-engine</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.powermock</groupId>
+            <artifactId>powermock-module-testng</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.powermock</groupId>
+            <artifactId>powermock-api-mockito</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
diff --git a/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/java/org/wso2/carbon/identity/jwt/client/extension/service/JWTClientTest.java b/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/java/org/wso2/carbon/identity/jwt/client/extension/service/JWTClientTest.java
index 33311c953d..a9c759e29e 100644
--- a/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/java/org/wso2/carbon/identity/jwt/client/extension/service/JWTClientTest.java
+++ b/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/java/org/wso2/carbon/identity/jwt/client/extension/service/JWTClientTest.java
@@ -19,18 +19,39 @@ package org.wso2.carbon.identity.jwt.client.extension.service;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpPost;
+import org.mockito.Mockito;
+import org.powermock.api.mockito.PowerMockito;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.testng.Assert;
+import org.testng.IObjectFactory;
 import org.testng.annotations.BeforeClass;
+import org.testng.annotations.ObjectFactory;
 import org.testng.annotations.Test;
 import org.wso2.carbon.identity.jwt.client.extension.JWTClient;
+import org.wso2.carbon.identity.jwt.client.extension.dto.AccessTokenInfo;
 import org.wso2.carbon.identity.jwt.client.extension.dto.JWTConfig;
 import org.wso2.carbon.identity.jwt.client.extension.exception.JWTClientException;
+import org.wso2.carbon.identity.jwt.client.extension.util.JWTClientUtil;
 
+import java.io.IOException;
+import java.security.KeyManagementException;
+import java.security.KeyStoreException;
+import java.security.NoSuchAlgorithmException;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Properties;
 
+@PrepareForTest(JWTClientUtil.class)
 public class JWTClientTest {
-    private static final Log log = LogFactory.getLog(JWTClientManagerServiceTest.class);
+    private static final Log log = LogFactory.getLog(JWTClientTest.class);
+
+    @ObjectFactory
+    public IObjectFactory getObjectFactory() {
+        return new org.powermock.modules.testng.PowerMockObjectFactory();
+    }
 
     private JWTClient jwtClient;
 
@@ -38,25 +59,158 @@ public class JWTClientTest {
     public void init() {
         Properties prop = new Properties();
         prop.put("default-jwt-client", "true");
+        prop.put("TokenEndpoint", "http://example.com");
         jwtClient = new JWTClient(new JWTConfig(prop));
     }
 
     @Test(description = "Test get JWT token.")
     public void testGetJwtToken() throws JWTClientException {
-        jwtClient.getJwtToken("admin");
+        String mockToken = "123456789";
+        PowerMockito.mockStatic(JWTClientUtil.class);
+        PowerMockito.when(JWTClientUtil.generateSignedJWTAssertion(Mockito.anyString(), Mockito.any(JWTConfig.class),
+                Mockito.anyBoolean())).thenReturn(mockToken);
+        String token = jwtClient.getJwtToken("admin");
+        Assert.assertEquals(token, mockToken);
     }
 
     @Test(description = "Test get JWT token by claims.")
     public void testGetJwtTokenByClaims() throws JWTClientException {
         Map<String, String> claims = new HashMap<>();
         claims.put("name", "admin");
-        jwtClient.getJwtToken("admin", claims);
+        String mockToken = "123456789";
+        PowerMockito.mockStatic(JWTClientUtil.class);
+        PowerMockito.when(JWTClientUtil.generateSignedJWTAssertion(Mockito.anyString(), Mockito.any(JWTConfig.class),
+                Mockito.anyBoolean(), Mockito.any())).thenReturn(mockToken);
+        String token = jwtClient.getJwtToken("admin", claims);
+        Assert.assertEquals(token, mockToken);
+    }
+
+    @Test(description = "Test get JWT token by tenant sign true.")
+    public void testGetJwtTokenByTenantSignTrue() throws JWTClientException {
+        Map<String, String> claims = new HashMap<>();
+        claims.put("name", "admin");
+        String mockToken = "123456789";
+        PowerMockito.mockStatic(JWTClientUtil.class);
+        PowerMockito.when(JWTClientUtil.generateSignedJWTAssertion(Mockito.anyString(), Mockito.any(JWTConfig.class),
+                Mockito.anyBoolean(), Mockito.any())).thenReturn(mockToken);
+        String token = jwtClient.getJwtToken("admin", claims, true);
+        Assert.assertEquals(token, mockToken);
     }
 
-    @Test(description = "Test get JWT token by tenant sign.")
-    public void testGetJwtTokenByTenantSign() throws JWTClientException {
+    @Test(description = "Test get JWT token by tenant sign false.")
+    public void testGetJwtTokenByTenantSignFalse() throws JWTClientException {
         Map<String, String> claims = new HashMap<>();
         claims.put("name", "admin");
-        jwtClient.getJwtToken("admin", claims, true);
+        String mockToken = "123456789";
+        PowerMockito.mockStatic(JWTClientUtil.class);
+        PowerMockito.when(JWTClientUtil.generateSignedJWTAssertion(Mockito.anyString(), Mockito.any(JWTConfig.class),
+                Mockito.anyBoolean(), Mockito.any())).thenReturn(mockToken);
+        String token = jwtClient.getJwtToken("admin", claims, false);
+        Assert.assertEquals(token, mockToken);
+    }
+
+    @Test(description = "Test get token info.")
+    public void testGetTokenInfo() throws KeyManagementException, NoSuchAlgorithmException, KeyStoreException,
+            IOException, JWTClientException {
+        mockJWTClientUtil();
+        AccessTokenInfo tokenInfo = jwtClient.getAccessToken("key", "secret", "admin", "default");
+        Assert.assertEquals(tokenInfo.getAccessToken(), "b7882d23f1f8257f4bc6cf4a20633ab1");
+    }
+
+    @Test(description = "Test get token info assertion null.")
+    public void testGetTokenInfoAssertionNull() throws KeyManagementException, NoSuchAlgorithmException,
+            KeyStoreException,
+            IOException {
+        HttpClient httpClient = Mockito.mock(HttpClient.class);
+        HttpResponse httpResponse = Mockito.mock(HttpResponse.class);
+        Mockito.when(httpClient.execute(Mockito.any(HttpPost.class))).thenReturn(httpResponse);
+
+        PowerMockito.mockStatic(JWTClientUtil.class);
+        try {
+            PowerMockito.when(JWTClientUtil.generateSignedJWTAssertion(Mockito.anyString(), Mockito.any(JWTConfig
+                            .class),
+
+                    Mockito.anyBoolean())).thenReturn(null);
+            PowerMockito.when(JWTClientUtil.getHttpClient(Mockito.anyString())).thenReturn(httpClient);
+            PowerMockito.when(JWTClientUtil.getResponseString(Mockito.any(HttpResponse.class))).thenReturn
+                    ("\n" +
+                            "{\n" +
+                            "    \"scope\":\"default\",\n" +
+                            "    \"token_type\":\"Bearer\",\n" +
+                            "    \"expires_in\":3600,\n" +
+                            "    \"refresh_token\":\"7ed6bae2b1d36c041787e8c8e2d6cbf8\",\n" +
+                            "    \"access_token\":\"b7882d23f1f8257f4bc6cf4a20633ab1\"\n" +
+                            "}");
+            jwtClient.getAccessToken("key", "secret", "admin", "default");
+            Assert.fail();
+        } catch (JWTClientException e) {
+            Assert.assertNotNull(e);
+        }
+    }
+
+    @Test(description = "Test get token info with encoded app credentials.")
+    public void testGetTokenInfoWithEncodeCredentials() throws KeyManagementException, NoSuchAlgorithmException,
+            KeyStoreException,
+            IOException, JWTClientException {
+        mockJWTClientUtil();
+        AccessTokenInfo tokenInfo = jwtClient.getAccessToken("a2V5OnNlY3JldA==", "admin", "default");
+        Assert.assertEquals(tokenInfo.getAccessToken(), "b7882d23f1f8257f4bc6cf4a20633ab1");
+    }
+
+    @Test(description = "Test get token info with invalid encoded app credentials.")
+    public void testGetTokenInfoWithInvalidEncodeCredentials() throws KeyManagementException,
+            NoSuchAlgorithmException, KeyStoreException,
+            IOException {
+        try {
+            mockJWTClientUtil();
+            jwtClient.getAccessToken("8s7d6fgh4j3", "admin", "default");
+            Assert.fail();
+        } catch (JWTClientException e) {
+            Assert.assertNotNull(e);
+        }
+    }
+
+    @Test(description = "Test get token info with name value pair.")
+    public void testGetTokenInfoWithNameValue() throws KeyManagementException, NoSuchAlgorithmException,
+            KeyStoreException,
+            IOException, JWTClientException {
+        mockJWTClientUtil();
+        Map<String, String> map = new HashMap();
+        map.put("admin", "admin");
+        AccessTokenInfo tokenInfo = jwtClient.getAccessToken("key", "secret", "admin", "default", map);
+        Assert.assertEquals(tokenInfo.getAccessToken(), "b7882d23f1f8257f4bc6cf4a20633ab1");
+    }
+
+    @Test(description = "Test get token from refresh token.")
+    public void testGetAccessTokenFromRefreshToken() throws KeyManagementException, NoSuchAlgorithmException,
+            KeyStoreException,
+            IOException, JWTClientException {
+        mockJWTClientUtil();
+        Map<String, String> map = new HashMap();
+        map.put("admin", "admin");
+        AccessTokenInfo tokenInfo = jwtClient.getAccessTokenFromRefreshToken("7ed6bae2b1d36c041787e8c8e2d6cbf8",
+                "admin", "default", "key", "secret");
+        Assert.assertEquals(tokenInfo.getAccessToken(), "b7882d23f1f8257f4bc6cf4a20633ab1");
+    }
+
+    private void mockJWTClientUtil() throws KeyManagementException, NoSuchAlgorithmException, KeyStoreException,
+            IOException, JWTClientException {
+        HttpClient httpClient = Mockito.mock(HttpClient.class);
+        HttpResponse httpResponse = Mockito.mock(HttpResponse.class);
+        Mockito.when(httpClient.execute(Mockito.any(HttpPost.class))).thenReturn(httpResponse);
+
+        PowerMockito.mockStatic(JWTClientUtil.class);
+        PowerMockito.when(JWTClientUtil.generateSignedJWTAssertion(Mockito.anyString(), Mockito.any(JWTConfig.class),
+                Mockito.anyBoolean())).thenReturn("b7882d23f1f8257f4bc6cf4a20633ab1");
+        PowerMockito.when(JWTClientUtil.getHttpClient(Mockito.anyString())).thenReturn(httpClient);
+        PowerMockito.when(JWTClientUtil.getResponseString(Mockito.any(HttpResponse.class))).thenReturn
+                ("\n" +
+                        "{\n" +
+                        "    \"scope\":\"default\",\n" +
+                        "    \"token_type\":\"Bearer\",\n" +
+                        "    \"expires_in\":3600,\n" +
+                        "    \"refresh_token\":\"7ed6bae2b1d36c041787e8c8e2d6cbf8\",\n" +
+                        "    \"access_token\":\"b7882d23f1f8257f4bc6cf4a20633ab1\"\n" +
+                        "}");
     }
 }
diff --git a/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/resources/log4j.properties b/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/resources/log4j.properties
index 90c5d0edce..7e18cfdc75 100644
--- a/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/resources/log4j.properties
+++ b/components/identity-extensions/org.wso2.carbon.identity.jwt.client.extension/src/test/resources/log4j.properties
@@ -25,7 +25,7 @@
 # settings will override the settings in this file.
 #
 
-log4j.rootLogger=DEBUG, STD_OUT
+log4j.rootLogger=INFO, STD_OUT
  
 # Redirect log messages to console
 log4j.appender.STD_OUT=org.apache.log4j.ConsoleAppender