optimize read csv

alibaba · Feb 9, 2025 · 5b34823 · 5b34823
1 parent c033ccf
commit 5b34823
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Showing 9 changed files with 486 additions and 255 deletions.
diff --git a/benchmark/src/test/java/com/alibaba/fastjson2/benchmark/CSVPersonTest.java b/benchmark/src/test/java/com/alibaba/fastjson2/benchmark/CSVPersonTest.java
@@ -15,8 +15,8 @@ public static void fastjson2() {
             long millis = System.currentTimeMillis() - start;
             System.out.println("fastjson2 millis : " + millis);
             // zulu8.68.0.21 : 3621 3270 2788 2424 2431 2123
-            // zulu11.62.17 : 2576 1848 2155 1567 1522
-            // zulu17.40.19 : 3501 3134 2586 2788 2733 2682
+            // zulu11.62.17 : 2576 1848 2155 1567 1522 1307
+            // zulu17.40.19 : 3501 3134 2586 2788 2733 2682 2494
         }
     }
 

diff --git a/core/src/main/java/com/alibaba/fastjson2/stream/JSONStreamReaderUTF8.java b/core/src/main/java/com/alibaba/fastjson2/stream/JSONStreamReaderUTF8.java
@@ -106,7 +106,7 @@ protected boolean seekLine() throws IOException {
             }
 
             if (!lineTerminated) {
-                if (input != null && !inputEnd) {
+                if (input != null && !(inputEnd && off >= end)) {
                     int len = end - off;
                     if (off > 0) {
                         if (len > 0) {
@@ -145,7 +145,7 @@ protected boolean seekLine() throws IOException {
 
     public <T> T readLineObject() {
         try {
-            if (inputEnd) {
+            if (inputEnd && off >= end) {
                 return null;
             }
 

diff --git a/core/src/main/java/com/alibaba/fastjson2/stream/StreamReader.java b/core/src/main/java/com/alibaba/fastjson2/stream/StreamReader.java
@@ -584,7 +584,7 @@ public boolean tryAdvance(Consumer<? super T> action) {
                 throw new IllegalArgumentException("action must not be null");
             }
             T object = next();
-            if (streamReader.inputEnd || object == null) {
+            if ((streamReader.inputEnd && streamReader.off >= streamReader.end) || object == null) {
                 return false;
             } else {
                 action.accept(object);
@@ -611,7 +611,7 @@ public Spliterator<T> trySplit() {
 
         @Override
         public long estimateSize() {
-            return streamReader.inputEnd ? 0L : Long.MAX_VALUE;
+            return (streamReader.inputEnd && streamReader.off >= streamReader.end) ? 0L : Long.MAX_VALUE;
         }
 
         @Override

diff --git a/core/src/main/java/com/alibaba/fastjson2/support/csv/CSVReader.java b/core/src/main/java/com/alibaba/fastjson2/support/csv/CSVReader.java
@@ -345,7 +345,7 @@ public T readLineObject() {
         if (!objectSupport) {
             throw new UnsupportedOperationException("this method should not be called, try specify objectClass or method readLineValues instead ?");
         }
-        if (inputEnd) {
+        if (inputEnd && off == end) {
             return null;
         }