Gradle project cannot be decompiled

[HelloThisWorld]

My gradle build script as below.

buildscript {
    ext {
        springBootVersion = '1.5.8.RELEASE'
        startClass='xxxx.xxx.xxx'
        buildType='sandbox'
        depotInfo='none'
    }
    repositories {
        jcenter()
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:1.4.2.RELEASE")
        classpath 'org.asciidoctor:asciidoctor-gradle-plugin:1.5.3'
        classpath 'org.ajoberstar:gradle-git-publish:0.3.2'
        classpath 'org.springframework.cloud:spring-cloud-contract-gradle-plugin:1.1.3.RELEASE'
    }
}

apply from: 'gradle/utils.gradle'
apply from: 'gradle/properties.gradle'

apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'idea'
apply plugin: 'org.springframework.boot'
apply plugin: 'org.asciidoctor.convert'
apply plugin: 'org.ajoberstar.git-publish'
apply plugin: 'war'

apply plugin: 'groovy'
apply plugin: 'spring-cloud-contract'

apply from: 'gradle/jacoco.gradle'
apply from: 'gradle/dependency-report.gradle'

def grgit = Grgit.open(dir: projectDir)

task generateGitProperties {
    def branchName = grgit.branch.current.name
    def gitHash = grgit.head().id
    def buildTime = new Date().toString()
    delete 'src/main/resources/git.properties'
    def text = "git.commit.id=${gitHash}\ngit.build.time=${buildTime}\ngit.branch=${branchName}"
    def git = new File('/Users/yiogao/code/epc-review-notification-service/src/main/resources/git.properties')
    git.text = text

    def active = new File('active.txt')
    active.text = "${gitHash}"

    version = gitHash
}

project.tasks.classes.dependsOn(generateGitProperties)

group = 'xxx.xxxx.xxx'
version = '1.0-SNAPSHOT'



repositories {
    mavenCentral()
    maven { url "xxx.xxx.xxx" }
}

configurations.all {
    exclude group: 'com.netflix.feign', module: 'feign-core'
    exclude group: 'com.netflix.feign', module: 'feign-jackson'
    exclude group: 'com.netflix.feign', module: 'feign-gson'
    exclude group: 'com.netflix.feign', module: 'feign-hystrix'
    exclude group: 'com.netflix.feign', module: 'feign-slf4j'
    exclude (module: 'spring-boot-starter-logging')
    exclude (module: "logback-classic")
    exclude (module: 'commons-logging')
}

sourceCompatibility = 1.8
targetCompatibility = 1.8

dependencies {
	xxx
}

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-contract-dependencies:1.1.3.RELEASE"
    }
}

contracts {
    testMode = 'MockMvc'
    packageWithBaseClasses = 'xxx.xxx.xxx'
    contractsDslDir = file("${project.projectDir}/src/test/resources/contracts/")
}


asciidoctor {
    sourceDir = file('src/main/docs')
    outputDir "$projectDir/src/main/resources/public"
    backends 'html5'
    attributes 'source-highlighter' : 'prettify'

}

task cleanTempDir(type: Delete) {
    delete fileTree(dir: 'src/main/resources/public')
}

clean {
    dependsOn cleanTempDir
}

build {
    dependsOn asciidoctor
}

task publish(type: GradleBuild) {
    dependsOn asciidoctor
    tasks = ['publishGhPages']
}

task wrapper(type: Wrapper) {
    gradleVersion = '4.2.1'
}

task contractTest(type: Test) {
    configure {
        systemProperty "contractTest.environment", System.getProperty("contractTest.environment")
        systemProperty "apiToken", System.getProperty("apiToken")
        systemProperty "remoteDriver", System.getProperty("remoteDriver")
    }
}

bootRun {
    dependsOn asciidoctor
    configure {
        systemProperty "AWS_REGION", System.getProperty("AWS_REGION")
        systemProperty "application.environment", "dev"
        systemProperty "spring.profiles.active", "dev"
        systemProperty "application.home", "."
    }
    jvmArgs=["-Dproject.name=${project.name}",
             "-Dapplication.name=${project.name}",
             '-Dapplication.environment=dev',
             '-Dapplication.home=.',
             '-Xdebug',
             '-Xrunjdwp:server=y,transport=dt_socket,address=5005,suspend=n']
}

war {
    manifest {
        attributes("Application-Name": "${project.name}",
                "Application-Version": "${project.version}",
                "Application-Description": "${project.description}",
                "Implementation-Title": "${project.name}",
                "Implementation-Version": "${grgit.head().id}",
                "Implementation-Vendor": "Expedia",
                "Built-By": System.getProperty("user.name"),
                "Build-Jdk": System.getProperty("java.version"),
                "Build-Time": new Date(),
                "Build": "${buildType}",
                "Branch": "${grgit.branch.current.name}",
                "Depot": "${depotInfo}",
                "mainClass": "${startClass}")
    }
}

My .classpath file

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
	<classpathentry kind="src" path="src/main/java"/>
	<classpathentry kind="src" path="src/main/resources"/>
	<classpathentry kind="src" path="src/test/java"/>
	<classpathentry kind="src" path="src/test/resources"/>
	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8/"/>
	<classpathentry kind="con" path="org.eclipse.jst.j2ee.internal.web.container"/>
	<classpathentry kind="con" path="org.eclipse.buildship.core.gradleclasspathcontainer">
		<attributes>
			<attribute name="org.eclipse.jst.component.dependency" value="/WEB-INF/lib"/>
		</attributes>
	</classpathentry>
	<classpathentry kind="output" path="bin"/>
</classpath>