more efficient persisting

core/src/main/groovy/com/muwire/core/files/PersisterService.groovy

@@ -103,10 +103,12 @@ class PersisterService extends Service {
 	private void persistFiles() {
 		location.delete()
 		def sharedFiles = fileSource.getSharedFiles()
-		sharedFiles.each { k, v -> 
-			def json = toJson(k,v)
-			json = JsonOutput.toJson(json)
-			location.append "$json\n"
+		location.withPrintWriter { writer ->
+			sharedFiles.each { k, v ->
+				def json = toJson(k,v)
+				json = JsonOutput.toJson(json)
+				writer.println json
+			}
 		}
 	}
 	

core/src/main/groovy/com/muwire/core/hostcache/HostCache.groovy

@@ -107,13 +107,15 @@ class HostCache extends Service {
 	
 	private void save() {
 		storage.delete()
-		hosts.each { dest, host ->
-			if (allowHost(host)) {
-				def map = [:]
-				map.destination = dest.toBase64()
-				map.failures = host.failures
-				def json = JsonOutput.toJson(map)
-				storage.append("${json}\n")
+		storage.withPrintWriter { writer ->
+			hosts.each { dest, host ->
+				if (allowHost(host)) {
+					def map = [:]
+					map.destination = dest.toBase64()
+					map.failures = host.failures
+					def json = JsonOutput.toJson(map)
+					writer.println json
+				}
 			}
 		}
 	}

core/src/main/groovy/com/muwire/core/trust/TrustService.groovy

@@ -49,12 +49,16 @@ class TrustService extends Service {
 	
 	private void persist() {
 		persistGood.delete()
-		good.each {
-			persistGood.append("${it.toBase64()}\n")
+		persistGood.withPrintWriter { writer ->
+			good.each {
+				writer.println it.toBase64()
+			}
 		}
 		persistBad.delete()
-		bad.each {
-			persistBad.append("${it.toBase64()}\n")
+		persistBad.withPrintWriter { writer ->
+			bad.each { 
+				writer.println it.toBase64()
+			}
 		}
 	}