Assignment Solutions

src/main/java/com/scaler/lld/design/assignments/builder/DatabaseConfigurationBuilder.java

@@ -2,5 +2,51 @@
 
 @WithBuilder
 public class DatabaseConfigurationBuilder {
+    private String databaseUrl;
+    private String username;
+    private String password;
+    private int maxConnections;
+    private boolean enableCache;
+    private boolean isReadOnly;
+    public static Builder builder(){ //static builder method
+        return new Builder();
+    }
+    private DatabaseConfigurationBuilder(){} //Private constructor
+    public static class Builder{
+
+        DatabaseConfigurationBuilder obj;
+        public Builder(){
+            obj=new DatabaseConfigurationBuilder();
+        }
+        public Builder setDatabaseUrl(String databaseUrl) {
+            obj.databaseUrl = databaseUrl; return this;
+        }
+
+        public Builder setUsername(String username) {
+            obj.username = username; return this;
+        }
+
+        public Builder setPassword(String password) {
+            obj.password = password; return this;
+        }
+
+        public Builder setMaxConnections(int maxConnections) {
+            obj.maxConnections = maxConnections; return this;
+        }
+
+        public Builder setEnableCache(boolean enableCache) {
+            obj.enableCache = enableCache; return this;
+        }
+
+        public Builder setReadOnly(boolean readOnly) {
+            obj.isReadOnly = readOnly; return this;
+        }
+        public DatabaseConfigurationBuilder build(){
+            return obj;
+        }
+
+    }
+
+
 
 }

src/main/java/com/scaler/lld/design/assignments/prototype/Configuration.java

@@ -1,6 +1,7 @@
 package com.scaler.lld.design.assignments.prototype;
+import java.io.ObjectInputFilter;
 
-public class Configuration {
+public class Configuration implements ClonableObject<Configuration>{
     private String themeColor;
     private Boolean autoSave;
     private String language;
@@ -18,6 +19,15 @@ public Configuration(String themeColor, Boolean autoSave, String language, Boole
         this.fontFamily = fontFamily;
         this.type = type;
     }
+    private Configuration(Configuration obj){
+        this.themeColor=obj.themeColor;
+        this.autoSave=obj.autoSave;
+        this.language=obj.language;
+        this.darkMode=obj.darkMode;
+        this.fontSize= obj.fontSize;
+        this.type=obj.type;
+        this.fontFamily=obj.fontFamily;
+    }
 
     public String getThemeColor() {
         return themeColor;
@@ -46,4 +56,9 @@ public String getFontFamily() {
     public ConfigurationType getType() {
         return type;
     }
+
+    @Override
+    public Configuration cloneObject() {
+        return new Configuration(this);
+    }
 }

src/main/java/com/scaler/lld/design/assignments/prototype/ConfigurationPrototypeRegistryImpl.java

@@ -0,0 +1,29 @@
+package com.scaler.lld.design.assignments.prototype;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class ConfigurationPrototypeRegistryImpl implements ConfigurationPrototypeRegistry{
+    Map<ConfigurationType, Configuration> registry=new HashMap<>();
+    @Override
+    public void addPrototype(Configuration user) {
+        registry.put(user.getType(), user);
+
+    }
+
+    @Override
+    public Configuration getPrototype(ConfigurationType type) {
+        return registry.get(type);
+    }
+
+    @Override
+    public Configuration clone(ConfigurationType type) {
+        if(registry.containsKey(type)){
+            Configuration prototype=registry.get(type);
+            return prototype.cloneObject();
+        }
+        else{
+            return null;
+        }
+    }
+}

src/main/java/com/scaler/lld/design/assignments/singleton/FileBasedConfigurationManagerImpl.java

@@ -1,50 +1,72 @@
 package com.scaler.lld.design.assignments.singleton;
 
 public class FileBasedConfigurationManagerImpl extends FileBasedConfigurationManager {
-
+    private static FileBasedConfigurationManagerImpl instance=null;
+    private FileBasedConfigurationManagerImpl(){
+    }
     @Override
     public String getConfiguration(String key) {
-        // TODO Auto-generated method stub
-        throw new UnsupportedOperationException("Unimplemented method 'getConfiguration'");
+        return this.properties.getProperty(key);
+        //throw new UnsupportedOperationException("Unimplemented method 'getConfiguration'");
     }
 
     @Override
     public <T> T getConfiguration(String key, Class<T> type) {
-        // TODO Auto-generated method stub
-        throw new UnsupportedOperationException("Unimplemented method 'getConfiguration'");
+        if(instance!=null){
+            String value=instance.properties.getProperty(key); //This retrieves the value
+            if(value!=null)
+                return convert(value,type);
+            else
+                return null;
+        }
+        else{
+            throw new NullPointerException("Configuration Manager Instance is NULL");
+        }
+        //throw new UnsupportedOperationException("Unimplemented method 'getConfiguration'");
+
     }
 
     @Override
     public void setConfiguration(String key, String value) {
-        // TODO Auto-generated method stub
-        throw new UnsupportedOperationException("Unimplemented method 'setConfiguration'");
+        this.properties.setProperty(key, value);
+        //throw new UnsupportedOperationException("Unimplemented method 'setConfiguration'");
+
     }
 
     @Override
     public <T> void setConfiguration(String key, T value) {
-        // TODO Auto-generated method stub
-        throw new UnsupportedOperationException("Unimplemented method 'setConfiguration'");
+        properties.setProperty(key, String.valueOf((value)));
+        //throw new UnsupportedOperationException("Unimplemented method 'setConfiguration'");
+
     }
 
     @Override
     public void removeConfiguration(String key) {
-        // TODO Auto-generated method stub
-        throw new UnsupportedOperationException("Unimplemented method 'removeConfiguration'");
+        properties.remove(key);
+        //throw new UnsupportedOperationException("Unimplemented method 'removeConfiguration'");
+
     }
 
     @Override
     public void clear() {
-        // TODO Auto-generated method stub
-        throw new UnsupportedOperationException("Unimplemented method 'clear'");
+        properties.clear();
+        //throw new UnsupportedOperationException("Unimplemented method 'clear'");
+
     }
 
     public static FileBasedConfigurationManager getInstance() {
-        // TODO Auto-generated method stub
-        return null;
+        if(instance==null){
+            synchronized (FileBasedConfigurationManagerImpl.class){
+                if(instance==null){
+                    instance=new FileBasedConfigurationManagerImpl();
+                }
+            }
+        }
+        return instance;
     }
 
     public static void resetInstance() {
-        // TODO Auto-generated method stub
+        instance=null;
     }
 
 }