diff --git a/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/PipeManagerWorker.java b/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/PipeManagerWorker.java
index af2689b..cafa2ee 100644
--- a/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/PipeManagerWorker.java
+++ b/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/PipeManagerWorker.java
@@ -189,10 +189,10 @@
 
   private int getNumOfPipeToWait(final RuntimeEdge runtimeEdge) {
     final int dstParallelism = ((StageEdge) runtimeEdge).getDstIRVertex().getPropertyValue(ParallelismProperty.class)
-      .orElseThrow(() -> new IllegalStateException());
+      .orElseThrow(IllegalStateException::new);
     final CommunicationPatternProperty.Value commPattern = ((StageEdge) runtimeEdge)
       .getPropertyValue(CommunicationPatternProperty.class)
-      .orElseThrow(() -> new IllegalStateException());
+      .orElseThrow(IllegalStateException::new);
 
     return commPattern.equals(CommunicationPatternProperty.Value.ONE_TO_ONE) ? 1 : dstParallelism;
   }
diff --git a/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/stores/GlusterFileStore.java b/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/stores/GlusterFileStore.java
index 6ca78b1..aff6e73 100644
--- a/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/stores/GlusterFileStore.java
+++ b/runtime/executor/src/main/java/org/apache/nemo/runtime/executor/data/stores/GlusterFileStore.java
@@ -80,10 +80,9 @@
    * Writes a committed block to this store.
    *
    * @param block the block to write.
-   * @throws BlockWriteException if fail to write.
    */
   @Override
-  public void writeBlock(final Block block) throws BlockWriteException {
+  public void writeBlock(final Block block) {
     if (!(block instanceof FileBlock)) {
       throw new BlockWriteException(new Throwable(
         this.toString() + " only accept " + FileBlock.class.getName()));
@@ -98,10 +97,9 @@
    *
    * @param blockId of the target partition.
    * @return the target block (if it exists).
-   * @throws BlockFetchException for any error occurred while trying to fetch a block.
    */
   @Override
-  public Optional<Block> readBlock(final String blockId) throws BlockFetchException {
+  public Optional<Block> readBlock(final String blockId) {
     final String filePath = DataUtil.blockIdToFilePath(blockId, fileDirectory);
     if (!new File(filePath).isFile()) {
       return Optional.empty();
@@ -122,7 +120,7 @@
    * @return whether the block exists or not.
    */
   @Override
-  public boolean deleteBlock(final String blockId) throws BlockFetchException {
+  public boolean deleteBlock(final String blockId) {
     final String filePath = DataUtil.blockIdToFilePath(blockId, fileDirectory);
 
     try {