Flutter Could not find method Properties() for arguments [] on project ':app' of type org.gradle.api.Project

Question

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '44'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '4.4'
}

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"

def keystoreProperties = Properties()
def keystorePropertiesFile = rootProject.file('key.properties')
if (keystorePropertiesFile.exists()) {
    keystoreProperties.load(FileInputStream(keystorePropertiesFile))
}


android {
    compileSdkVersion 29

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    lintOptions {
        disable 'InvalidPackage'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.credfinance.credfinance"
        minSdkVersion 19
        targetSdkVersion 29
        versionCode 44
        versionName '4.4'
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    signingConfigs {
        release {
            keyAlias keystoreProperties['keyAlias']
            keyPassword keystoreProperties['keyPassword']
            storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
            storePassword keystoreProperties['storePassword']
        }
   }
   buildTypes {
       release {
           signingConfig signingConfigs.release
       }
   }
}

flutter {
    source '../..'
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
}

OUT PUT:

mac@Macs-MacBook-Air credapp % flutter run Launching lib/main.dart on SM N950U in debug mode...

FAILURE: Build failed with an exception.

• Where:
  Build file '/Users/mac/Documents/Flutter_Project/credapp/android/app/build.gradle' line: 28

• What went wrong:
  A problem occurred evaluating project ':app'.

  Could not find method Properties() for arguments [] on project ':app' of type org.gradle.api.Project.

• Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

• Get more help at https://help.gradle.org

BUILD FAILED in 0s
Running Gradle task 'assembleDebug'...
Running Gradle task 'assembleDebug'... Done 2.8s Exception: Gradle task assembleDebug failed with exit code 1 mac@Macs-MacBook-Air credapp %

Answer 1

add 'new' keyword wherever its throwing the problem.

For me

if (keystorePropertiesFile.exists()) {
    keystoreProperties.load(  FileInputStream(keystorePropertiesFile))} 

was throwing error

if (keystorePropertiesFile.exists()) {
    keystoreProperties.load( new FileInputStream(keystorePropertiesFile))}

saved the day