diff --git a/physics-engine/src/main/java/com/project/physics/engine/graphic/DynamicCamera.java b/physics-engine/src/main/java/com/project/physics/engine/graphic/DynamicCamera.java
index 4dd8047..911daed 100644
--- a/physics-engine/src/main/java/com/project/physics/engine/graphic/DynamicCamera.java
+++ b/physics-engine/src/main/java/com/project/physics/engine/graphic/DynamicCamera.java
@@ -53,6 +53,7 @@
 import com.project.physics.engine.graphic.shader.Color;
 import com.project.physics.engine.graphic.shader.Shader;
 import com.project.physics.engine.graphic.shader.ShaderProgram;
+import com.project.physics.engine.graphic.shader.ShaderProgram.ShaderLocations;
 import com.project.physics.engine.graphic.shader.Texture;
 import com.project.physics.engine.math.Matrix4f;
 import com.project.physics.engine.text.Font;
@@ -455,17 +456,17 @@ private void setupShaderProgram() {
         specifyVertexAttributes();
 
         /* Set texture uniform */
-        int uniTex = program.getUniformLocation("texImage");
+        int uniTex = program.getUniformLocation(ShaderLocations.TEX_IMAGE);
         program.setUniform(uniTex, 0);
 
         /* Set model matrix to identity matrix */
         Matrix4f model = new Matrix4f();
-        int uniModel = program.getUniformLocation("model");
+        int uniModel = program.getUniformLocation(ShaderLocations.MODEL);
         program.setUniform(uniModel, model);
 
         /* Set view matrix to identity matrix */
         Matrix4f view = new Matrix4f();
-        int uniView = program.getUniformLocation("view");
+        int uniView = program.getUniformLocation(ShaderLocations.VIEW);
         program.setUniform(uniView, view);
 
         setProjection(width, height);
@@ -474,7 +475,7 @@ private void setupShaderProgram() {
     public void setProjection(int width, int height) {
         /* Set projection matrix to an orthographic projection */
         Matrix4f projection = Matrix4f.orthographic(0f, width, 0f, height, -1f, 1f);
-        int uniformProjection = program.getUniformLocation("projection");
+        int uniformProjection = program.getUniformLocation(ShaderLocations.PROJECTION);
         program.setUniform(uniformProjection, projection);
     }
 
@@ -483,17 +484,17 @@ public void setProjection(int width, int height) {
      */
     private void specifyVertexAttributes() {
         /* Specify Vertex Pointer */
-        int posAttrib = program.getAttributeLocation("position");
+        int posAttrib = program.getAttributeLocation(ShaderLocations.POSITION);
         program.enableVertexAttribute(posAttrib);
         program.pointVertexAttribute(posAttrib, 2, 8 * Float.BYTES, 0);
 
         /* Specify Color Pointer */
-        int colAttrib = program.getAttributeLocation("color");
+        int colAttrib = program.getAttributeLocation(ShaderLocations.COLOR);
         program.enableVertexAttribute(colAttrib);
         program.pointVertexAttribute(colAttrib, 4, 8 * Float.BYTES, 2 * Float.BYTES);
 
         /* Specify Texture Pointer */
-        int texAttrib = program.getAttributeLocation("texcoord");
+        int texAttrib = program.getAttributeLocation(ShaderLocations.TEX_COORD);
         program.enableVertexAttribute(texAttrib);
         program.pointVertexAttribute(texAttrib, 2, 8 * Float.BYTES, 6 * Float.BYTES);
     }
diff --git a/physics-engine/src/main/java/com/project/physics/engine/graphic/shader/ShaderProgram.java b/physics-engine/src/main/java/com/project/physics/engine/graphic/shader/ShaderProgram.java
index 6657e3d..235fe82 100644
--- a/physics-engine/src/main/java/com/project/physics/engine/graphic/shader/ShaderProgram.java
+++ b/physics-engine/src/main/java/com/project/physics/engine/graphic/shader/ShaderProgram.java
@@ -105,14 +105,14 @@ public void link() {
     }
 
     /**
-     * Gets the location of an attribute variable with specified name.
+     * Gets the location of an attribute variable with specified dataLocation.
      *
-     * @param name Attribute name
+     * @param dataLocation Attribute dataLocation
      *
      * @return Location of the attribute
      */
-    public int getAttributeLocation(CharSequence name) {
-        return glGetAttribLocation(id, name);
+    public int getAttributeLocation(ShaderLocations dataLocation) {
+        return glGetAttribLocation(id, dataLocation.toString());
     }
 
     /**
@@ -154,8 +154,8 @@ public void pointVertexAttribute(int location, int size, int stride, int offset)
      *
      * @return Location of the uniform
      */
-    public int getUniformLocation(CharSequence name) {
-        return glGetUniformLocation(id, name);
+    public int getUniformLocation(ShaderLocations name) {
+        return glGetUniformLocation(id, name.toString());
     }
 
     /**
@@ -276,4 +276,13 @@ public void delete() {
         glDeleteProgram(id);
     }
 
+    public enum ShaderLocations {
+        TEX_IMAGE,
+        MODEL,
+        VIEW,
+        PROJECTION,
+        POSITION,
+        COLOR,
+        TEX_COORD;
+    }
 }
diff --git a/physics-engine/src/main/java/com/project/physics/engine/state/SpinningTriangleState.java b/physics-engine/src/main/java/com/project/physics/engine/state/SpinningTriangleState.java
index 698a03a..3b49939 100644
--- a/physics-engine/src/main/java/com/project/physics/engine/state/SpinningTriangleState.java
+++ b/physics-engine/src/main/java/com/project/physics/engine/state/SpinningTriangleState.java
@@ -41,6 +41,7 @@
 import com.project.physics.engine.graphic.VertexBufferObject;
 import com.project.physics.engine.graphic.shader.Shader;
 import com.project.physics.engine.graphic.shader.ShaderProgram;
+import com.project.physics.engine.graphic.shader.ShaderProgram.ShaderLocations;
 import com.project.physics.engine.math.Matrix4f;
 
 /**
@@ -149,11 +150,11 @@ public void enter() {
         specifyVertexAttributes();
 
         /* Get uniform location for the model matrix */
-        uniModel = program.getUniformLocation("model");
+        uniModel = program.getUniformLocation(ShaderLocations.MODEL);
 
         /* Set view matrix to identity matrix */
         Matrix4f view = new Matrix4f();
-        int uniView = program.getUniformLocation("view");
+        int uniView = program.getUniformLocation(ShaderLocations.VIEW);
         program.setUniform(uniView, view);
 
         /* Get width and height for calculating the ratio */
@@ -168,7 +169,7 @@ public void enter() {
 
         /* Set projection matrix to an orthographic projection */
         Matrix4f projection = Matrix4f.orthographic(-ratio, ratio, -1f, 1f, -1f, 1f);
-        int uniProjection = program.getUniformLocation("projection");
+        int uniProjection = program.getUniformLocation(ShaderLocations.PROJECTION);
         program.setUniform(uniProjection, projection);
     }
 
@@ -186,12 +187,12 @@ public void exit() {
      */
     private void specifyVertexAttributes() {
         /* Specify Vertex Pointer */
-        int posAttrib = program.getAttributeLocation("position");
+        int posAttrib = program.getAttributeLocation(ShaderLocations.POSITION);
         program.enableVertexAttribute(posAttrib);
         program.pointVertexAttribute(posAttrib, 3, 6 * Float.BYTES, 0);
 
         /* Specify Color Pointer */
-        int colAttrib = program.getAttributeLocation("color");
+        int colAttrib = program.getAttributeLocation(ShaderLocations.COLOR);
         program.enableVertexAttribute(colAttrib);
         program.pointVertexAttribute(colAttrib, 3, 6 * Float.BYTES, 3 * Float.BYTES);
     }