Extract util methods to separate classes

src/main/java/org/asamk/signal/util/DateUtils.java

@@ -0,0 +1,21 @@
+package org.asamk.signal.util;
+
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.TimeZone;
+
+public class DateUtils {
+
+    private static final TimeZone tzUTC = TimeZone.getTimeZone("UTC");
+
+    private DateUtils() {
+    }
+
+    public static String formatTimestamp(long timestamp) {
+        Date date = new Date(timestamp);
+        final DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"); // Quoted "Z" to indicate UTC, no timezone offset
+        df.setTimeZone(tzUTC);
+        return timestamp + " (" + df.format(date) + ")";
+    }
+}

src/main/java/org/asamk/signal/util/Hex.java

@@ -6,6 +6,9 @@ public class Hex {
             '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
     };
 
+    private Hex() {
+    }
+
     public static String toStringCondensed(byte[] bytes) {
         StringBuffer buf = new StringBuffer();
         for (int i = 0; i < bytes.length; i++) {

src/main/java/org/asamk/signal/util/IOUtils.java

@@ -0,0 +1,55 @@
+package org.asamk.signal.util;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.StringWriter;
+import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.attribute.PosixFilePermission;
+import java.nio.file.attribute.PosixFilePermissions;
+import java.util.EnumSet;
+import java.util.Set;
+
+import static java.nio.file.attribute.PosixFilePermission.*;
+
+public class IOUtils {
+
+    private IOUtils() {
+    }
+
+    public static File createTempFile() throws IOException {
+        return File.createTempFile("signal_tmp_", ".tmp");
+    }
+
+    public static String readAll(InputStream in, Charset charset) throws IOException {
+        StringWriter output = new StringWriter();
+        byte[] buffer = new byte[4096];
+        int n;
+        while (-1 != (n = in.read(buffer))) {
+            output.write(new String(buffer, 0, n, charset));
+        }
+        return output.toString();
+    }
+
+    public static void createPrivateDirectories(String path) throws IOException {
+        final Path file = new File(path).toPath();
+        try {
+            Set<PosixFilePermission> perms = EnumSet.of(OWNER_READ, OWNER_WRITE, OWNER_EXECUTE);
+            Files.createDirectories(file, PosixFilePermissions.asFileAttribute(perms));
+        } catch (UnsupportedOperationException e) {
+            Files.createDirectories(file);
+        }
+    }
+
+    public static void createPrivateFile(String path) throws IOException {
+        final Path file = new File(path).toPath();
+        try {
+            Set<PosixFilePermission> perms = EnumSet.of(OWNER_READ, OWNER_WRITE);
+            Files.createFile(file, PosixFilePermissions.asFileAttribute(perms));
+        } catch (UnsupportedOperationException e) {
+            Files.createFile(file);
+        }
+    }
+}

src/main/java/org/asamk/signal/util/Util.java

@@ -1,10 +1,56 @@
 package org.asamk.signal.util;
 
-import java.io.File;
-import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.net.URLDecoder;
+import java.util.HashMap;
+import java.util.Map;
 
 public class Util {
-    public static File createTempFile() throws IOException {
-        return File.createTempFile("signal_tmp_", ".tmp");
+
+    private Util() {
+    }
+
+    public static String formatSafetyNumber(String digits) {
+        final int partCount = 12;
+        int partSize = digits.length() / partCount;
+        StringBuilder f = new StringBuilder(digits.length() + partCount);
+        for (int i = 0; i < partCount; i++) {
+            f.append(digits, i * partSize, (i * partSize) + partSize).append(" ");
+        }
+        return f.toString();
+    }
+
+    public static Map<String, String> getQueryMap(String query) {
+        String[] params = query.split("&");
+        Map<String, String> map = new HashMap<>();
+        for (String param : params) {
+            String name = null;
+            final String[] paramParts = param.split("=");
+            try {
+                name = URLDecoder.decode(paramParts[0], "utf-8");
+            } catch (UnsupportedEncodingException e) {
+                // Impossible
+            }
+            String value = null;
+            try {
+                value = URLDecoder.decode(paramParts[1], "utf-8");
+            } catch (UnsupportedEncodingException e) {
+                // Impossible
+            }
+            map.put(name, value);
+        }
+        return map;
+    }
+
+    public static String join(CharSequence separator, Iterable<? extends CharSequence> list) {
+        StringBuilder buf = new StringBuilder();
+        for (CharSequence str : list) {
+            if (buf.length() > 0) {
+                buf.append(separator);
+            }
+            buf.append(str);
+        }
+
+        return buf.toString();
     }
 }