Remove some low-hanging Guava from core/main (#1048)

core/src/main/kotlin/net/corda/core/concurrent/ConcurrencyUtils.kt

@@ -1,9 +1,9 @@
 package net.corda.core.concurrent
 
-import com.google.common.annotations.VisibleForTesting
 import com.google.common.util.concurrent.ListenableFuture
 import com.google.common.util.concurrent.SettableFuture
 import net.corda.core.catch
+import net.corda.core.internal.VisibleForTesting
 import net.corda.core.match
 import net.corda.core.then
 import org.slf4j.Logger

core/src/main/kotlin/net/corda/core/contracts/UniqueIdentifier.kt

@@ -1,6 +1,6 @@
 package net.corda.core.contracts
 
-import com.google.common.annotations.VisibleForTesting
+import net.corda.core.internal.VisibleForTesting
 import net.corda.core.serialization.CordaSerializable
 import java.util.*
 

core/src/main/kotlin/net/corda/core/crypto/SecureHash.kt

@@ -1,8 +1,9 @@
 package net.corda.core.crypto
 
-import com.google.common.io.BaseEncoding
 import net.corda.core.serialization.CordaSerializable
 import net.corda.core.utilities.OpaqueBytes
+import net.corda.core.utilities.parseAsHex
+import net.corda.core.utilities.toHexString
 import java.security.MessageDigest
 
 /**
@@ -18,7 +19,7 @@ sealed class SecureHash(bytes: ByteArray) : OpaqueBytes(bytes) {
         }
     }
 
-    override fun toString(): String = BaseEncoding.base16().encode(bytes)
+    override fun toString(): String = bytes.toHexString()
 
     fun prefixChars(prefixLen: Int = 6) = toString().substring(0, prefixLen)
     fun hashConcat(other: SecureHash) = (this.bytes + other.bytes).sha256()
@@ -26,7 +27,7 @@ sealed class SecureHash(bytes: ByteArray) : OpaqueBytes(bytes) {
     // Like static methods in Java, except the 'companion' is a singleton that can have state.
     companion object {
         @JvmStatic
-        fun parse(str: String) = BaseEncoding.base16().decode(str.toUpperCase()).let {
+        fun parse(str: String) = str.toUpperCase().parseAsHex().let {
             when (it.size) {
                 32 -> SHA256(it)
                 else -> throw IllegalArgumentException("Provided string is ${it.size} bytes not 32 bytes in hex: $str")

core/src/main/kotlin/net/corda/core/internal/InternalUtils.kt

@@ -1,6 +1,5 @@
 package net.corda.core.internal
 
-import com.google.common.base.Throwables
 import net.corda.core.crypto.SecureHash
 import net.corda.core.crypto.sha256
 import org.slf4j.Logger
@@ -8,10 +7,7 @@ import rx.Observable
 import rx.Observer
 import rx.subjects.PublishSubject
 import rx.subjects.UnicastSubject
-import java.io.ByteArrayInputStream
-import java.io.ByteArrayOutputStream
-import java.io.InputStream
-import java.io.OutputStream
+import java.io.*
 import java.lang.reflect.Field
 import java.math.BigDecimal
 import java.nio.charset.Charset
@@ -30,7 +26,8 @@ import java.util.zip.ZipEntry
 import java.util.zip.ZipOutputStream
 import kotlin.reflect.KClass
 
-inline val Throwable.rootCause: Throwable get() = Throwables.getRootCause(this)
+val Throwable.rootCause: Throwable get() = cause?.rootCause ?: this
+fun Throwable.getStackTraceAsString() = StringWriter().also { printStackTrace(PrintWriter(it)) }.toString()
 
 infix fun Temporal.until(endExclusive: Temporal): Duration = Duration.between(this, endExclusive)
 
@@ -249,3 +246,13 @@ class DeclaredField<T>(clazz: Class<*>, name: String, private val receiver: Any?
         get() = javaField.get(receiver) as T
         set(value) = javaField.set(receiver, value)
 }
+
+/** The annotated object would have a more restricted visibility were it not needed in tests. */
+@Target(AnnotationTarget.CLASS,
+        AnnotationTarget.PROPERTY,
+        AnnotationTarget.CONSTRUCTOR,
+        AnnotationTarget.FUNCTION,
+        AnnotationTarget.TYPEALIAS)
+@Retention(AnnotationRetention.SOURCE)
+@MustBeDocumented
+annotation class VisibleForTesting

core/src/main/kotlin/net/corda/core/node/ServiceHub.kt

@@ -1,6 +1,5 @@
 package net.corda.core.node
 
-import com.google.common.collect.Lists
 import net.corda.core.contracts.*
 import net.corda.core.crypto.DigitalSignature
 import net.corda.core.node.services.*
@@ -76,7 +75,7 @@ interface ServiceHub : ServicesForResolution {
      * further processing. This is expected to be run within a database transaction.
      */
     fun recordTransactions(first: SignedTransaction, vararg remaining: SignedTransaction) {
-        recordTransactions(Lists.asList(first, remaining))
+        recordTransactions(listOf(first, *remaining))
     }
 
     /**

core/src/main/kotlin/net/corda/core/serialization/Kryo.kt

@@ -4,11 +4,11 @@ import com.esotericsoftware.kryo.*
 import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
 import com.esotericsoftware.kryo.util.MapReferenceResolver
-import com.google.common.annotations.VisibleForTesting
 import net.corda.core.contracts.*
 import net.corda.core.crypto.*
 import net.corda.core.crypto.composite.CompositeKey
 import net.corda.core.identity.Party
+import net.corda.core.internal.VisibleForTesting
 import net.corda.core.transactions.CoreTransaction
 import net.corda.core.transactions.NotaryChangeWireTransaction
 import net.corda.core.transactions.SignedTransaction

core/src/main/kotlin/net/corda/core/serialization/amqp/DeserializationInput.kt

@@ -1,6 +1,6 @@
 package net.corda.core.serialization.amqp
 
-import com.google.common.base.Throwables
+import net.corda.core.internal.getStackTraceAsString
 import net.corda.core.serialization.SerializedBytes
 import org.apache.qpid.proton.amqp.Binary
 import org.apache.qpid.proton.amqp.DescribedType
@@ -92,7 +92,7 @@ class DeserializationInput(internal val serializerFactory: SerializerFactory = S
         } catch(nse: NotSerializableException) {
             throw nse
         } catch(t: Throwable) {
-            throw NotSerializableException("Unexpected throwable: ${t.message} ${Throwables.getStackTraceAsString(t)}")
+            throw NotSerializableException("Unexpected throwable: ${t.message} ${t.getStackTraceAsString()}")
         } finally {
             objectHistory.clear()
         }

core/src/main/kotlin/net/corda/core/utilities/ByteArrays.kt

@@ -2,9 +2,9 @@
 
 package net.corda.core.utilities
 
-import com.google.common.io.BaseEncoding
 import net.corda.core.serialization.CordaSerializable
 import java.io.ByteArrayInputStream
+import javax.xml.bind.DatatypeConverter
 
 /**
  * An abstraction of a byte array, with offset and size that does no copying of bytes unless asked to.
@@ -109,7 +109,7 @@ sealed class ByteSequence : Comparable<ByteSequence> {
         return result
     }
 
-    override fun toString(): String = "[${BaseEncoding.base16().encode(bytes, offset, size)}]"
+    override fun toString(): String = "[${bytes.copyOfRange(offset, offset + size).toHexString()}]"
 }
 
 /**
@@ -136,12 +136,12 @@ fun ByteArray.opaque(): OpaqueBytes = OpaqueBytes(this)
 
 fun ByteArray.sequence(offset: Int = 0, size: Int = this.size) = ByteSequence.of(this, offset, size)
 
-fun ByteArray.toHexString(): String = BaseEncoding.base16().encode(this)
-fun String.parseAsHex(): ByteArray = BaseEncoding.base16().decode(this)
+fun ByteArray.toHexString(): String = DatatypeConverter.printHexBinary(this)
+fun String.parseAsHex(): ByteArray = DatatypeConverter.parseHexBinary(this)
 
 private class OpaqueBytesSubSequence(override val bytes: ByteArray, override val offset: Int, override val size: Int) : ByteSequence() {
     init {
         require(offset >= 0 && offset < bytes.size)
         require(size >= 0 && size <= bytes.size)
     }
-}
+}

core/src/main/kotlin/net/corda/core/utilities/NonEmptySet.kt

@@ -1,6 +1,5 @@
 package net.corda.core.utilities
 
-import com.google.common.collect.Iterators
 import java.util.*
 import java.util.function.Consumer
 import java.util.stream.Stream
@@ -50,7 +49,7 @@ class NonEmptySet<T> private constructor(private val elements: Set<T>) : Set<T>
     /** Returns the first element of the set. */
     fun head(): T = elements.iterator().next()
     override fun isEmpty(): Boolean = false
-    override fun iterator(): Iterator<T> = Iterators.unmodifiableIterator(elements.iterator())
+    override fun iterator() = object : Iterator<T> by elements.iterator() {}
 
     // Following methods are not delegated by Kotlin's Class delegation
     override fun forEach(action: Consumer<in T>) = elements.forEach(action)