Allow input streams to be read

1 files changed, 46 insertions, 0 deletions

diff --git a/src/main/java/org/zwobble/mammoth/docx/InMemoryDocxFile.java b/src/main/java/org/zwobble/mammoth/docx/InMemoryDocxFile.java
new file mode 100644
index 0000000..3c6d4b4
--- /dev/null
+++ b/src/main/java/org/zwobble/mammoth/docx/InMemoryDocxFile.java
@@ -0,0 +1,46 @@
+package org.zwobble.mammoth.docx;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Maps;
+import com.google.common.io.ByteStreams;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+import java.util.Optional;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
+
+public class InMemoryDocxFile implements DocxFile {
+    public static DocxFile fromStream(InputStream stream) throws IOException {
+        ZipInputStream zipStream = new ZipInputStream(stream);
+        ImmutableMap.Builder<String, byte[]> entries = ImmutableMap.builder();
+        ZipEntry entry;
+        while ((entry = zipStream.getNextEntry()) != null) {
+            entries.put(entry.getName(), ByteStreams.toByteArray(zipStream));
+        }
+        return new InMemoryDocxFile(entries.build());
+    }
+
+    public static DocxFile fromStrings(Map<String, String> entries) {
+        return new InMemoryDocxFile(Maps.transformValues(entries, value -> value.getBytes(StandardCharsets.UTF_8)));
+    }
+
+    private final Map<String, byte[]> entries;
+
+    public InMemoryDocxFile(Map<String, byte[]> entries) {
+        this.entries = entries;
+    }
+
+    @Override
+    public Optional<InputStream> tryGetInputStream(String name) throws IOException {
+        return Optional.ofNullable(entries.get(name))
+            .map(ByteArrayInputStream::new);
+    }
+
+    @Override
+    public void close() throws IOException {
+    }
+}