Move from java/ to kotlin/ directory

Android 12 dynamic color usage on login screen

app/src/main/kotlin/com/meloda/fast/database/QueryBuilder.kt

@@ -0,0 +1,71 @@
+package com.meloda.fast.database
+
+import android.database.Cursor
+import android.database.sqlite.SQLiteDatabase
+
+
+class QueryBuilder private constructor() {
+
+    companion object {
+        fun query(): QueryBuilder {
+            return QueryBuilder()
+        }
+    }
+
+    private val builder: StringBuilder = StringBuilder()
+
+    fun select(column: String): QueryBuilder {
+        builder.append("SELECT ")
+            .append(column)
+            .append(" ")
+        return this
+    }
+
+    fun from(table: String): QueryBuilder {
+        builder.append("FROM ")
+            .append(table)
+            .append(" ")
+        return this
+    }
+
+
+    fun where(clause: String): QueryBuilder {
+        builder.append("WHERE ")
+            .append(clause)
+            .append(" ")
+        return this
+    }
+
+    fun leftJoin(table: String): QueryBuilder {
+        builder.append("LEFT JOIN ")
+            .append(table)
+            .append(" ")
+        return this
+    }
+
+    fun on(where: String): QueryBuilder {
+        builder.append("ON ")
+            .append(where)
+            .append(" ")
+        return this
+    }
+
+    fun and(): QueryBuilder {
+        builder.append("AND ")
+        return this
+    }
+
+    fun or(): QueryBuilder {
+        builder.append("OR ")
+        return this
+    }
+
+    fun asCursor(db: SQLiteDatabase): Cursor {
+        return db.rawQuery(toString(), null)
+    }
+
+    override fun toString(): String {
+        return builder.toString().trim()
+    }
+
+}