Merge pull request #285 from LokeshN/readtext-jsonparser1

issue #15 - readtext in jsonparser
FasterXML · May 18, 2016 · 7a0991a · 7a0991a
2 parents 780394c + ca17d2f
commit 7a0991a
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diff --git a/src/main/java/com/fasterxml/jackson/core/JsonParser.java b/src/main/java/com/fasterxml/jackson/core/JsonParser.java
@@ -1030,6 +1030,16 @@ public int currentTokenId() {
      */
     public abstract String getText() throws IOException;
 
+    /**
+     * Method to read the textual representation of the current token in chunks and 
+     * pass it to the given Writer
+     * 
+     *  @return The number of characters written to the Writer 
+     *  
+     *  @since 2.8
+     */
+    public abstract int readText(Writer writer) throws IOException, UnsupportedOperationException;
+
     /**
      * Method similar to {@link #getText}, but that will return
      * underlying (unmodifiable) character array that contains

diff --git a/src/main/java/com/fasterxml/jackson/core/json/ReaderBasedJsonParser.java b/src/main/java/com/fasterxml/jackson/core/json/ReaderBasedJsonParser.java
@@ -1,6 +1,7 @@
 package com.fasterxml.jackson.core.json;
 
 import java.io.*;
+import java.util.List;
 
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.base.ParserBase;
@@ -273,6 +274,51 @@ public final String getText() throws IOException
         return _getText2(t);
     }
 
+    @Override
+    public final int readText(Writer writer) throws IOException, UnsupportedOperationException {
+        JsonToken t = _currToken;
+        //Stores the length of the bytes read
+        int len = 0;
+        if (t == JsonToken.VALUE_STRING) {
+            if (_tokenIncomplete) {
+                _tokenIncomplete = false;
+                _finishString(); // only strings can be incomplete
+            }
+            List<char[]> segments = _textBuffer.getCharacterSegments();
+
+            //Indicates the currently read text buffer index which refers to the 
+            //TextBuffer character segment
+            int readTextBufferIndex = 0;
+            //if there are character segments, then use them and write them to the writer
+            while(segments != null && readTextBufferIndex < segments.size()) {
+                writer.write(segments.get(readTextBufferIndex));
+                len += segments.get(readTextBufferIndex).length;
+                readTextBufferIndex++;
+            }
+            //if there are no character segments left, then read the string from the current segment, and 
+            //write them directly to the buffer
+            writer.write(_textBuffer.getCurrentSegment(), 0, _textBuffer.getCurrentSegmentSize());
+            len += _textBuffer.getCurrentSegmentSize();
+
+        }
+        else if(t != null) {
+            switch (t.id()) {
+            case ID_FIELD_NAME:
+                writer.write(_parsingContext.getCurrentName());
+                break;    
+            case ID_STRING:
+            case ID_NUMBER_INT:
+            case ID_NUMBER_FLOAT:
+                writer.write(_textBuffer.contentsAsString());
+                break;
+            default:
+                writer.write(t.asString());
+            }
+        }
+
+        return len;
+    }
+
     // // // Let's override default impls for improved performance
 
     // @since 2.1

diff --git a/src/main/java/com/fasterxml/jackson/core/json/UTF8DataInputJsonParser.java b/src/main/java/com/fasterxml/jackson/core/json/UTF8DataInputJsonParser.java
@@ -2,6 +2,7 @@
 
 import java.io.*;
 import java.util.Arrays;
+import java.util.List;
 
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.base.ParserBase;
@@ -184,6 +185,51 @@ public String getText() throws IOException
         return _getText2(_currToken);
     }
 
+    @Override
+    public final int readText(Writer writer) throws IOException, UnsupportedOperationException {
+        JsonToken t = _currToken;
+        //Stores the length of the bytes read
+        int len = 0;
+        if (t == JsonToken.VALUE_STRING) {
+            if (_tokenIncomplete) {
+                _tokenIncomplete = false;
+                _finishString(); // only strings can be incomplete
+            }
+            List<char[]> segments = _textBuffer.getCharacterSegments();
+
+            //Indicates the currently read text buffer index which refers to the 
+            //TextBuffer character segment
+            int readTextBufferIndex = 0;
+            //if there are character segments, then use them and write them to the writer
+            while(segments != null && readTextBufferIndex < segments.size()) {
+                writer.write(segments.get(readTextBufferIndex));
+                len += segments.get(readTextBufferIndex).length;
+                readTextBufferIndex++;
+            }
+            //if there are no character segments left, then read the string from the current segment, and 
+            //write them directly to the buffer
+            writer.write(_textBuffer.getCurrentSegment(), 0, _textBuffer.getCurrentSegmentSize());
+            len += _textBuffer.getCurrentSegmentSize();
+
+        }
+        else if(t != null) {
+            switch (t.id()) {
+            case ID_FIELD_NAME:
+                writer.write(_parsingContext.getCurrentName());
+                break;    
+            case ID_STRING:
+            case ID_NUMBER_INT:
+            case ID_NUMBER_FLOAT:
+                writer.write(_textBuffer.contentsAsString());
+                break;
+            default:
+                writer.write(t.asString());
+            }
+        }
+
+        return len;
+    }
+
     // // // Let's override default impls for improved performance
     @Override
     public String getValueAsString() throws IOException

diff --git a/src/main/java/com/fasterxml/jackson/core/json/UTF8StreamJsonParser.java b/src/main/java/com/fasterxml/jackson/core/json/UTF8StreamJsonParser.java
@@ -2,6 +2,7 @@
 
 import java.io.*;
 import java.util.Arrays;
+import java.util.List;
 
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.base.ParserBase;
@@ -318,6 +319,51 @@ public String getText() throws IOException
         }
         return _getText2(_currToken);
     }
+
+    @Override
+    public final int readText(Writer writer) throws IOException, UnsupportedOperationException {
+        JsonToken t = _currToken;
+        //Stores the length of the bytes read
+        int len = 0;
+        if (t == JsonToken.VALUE_STRING) {
+            if (_tokenIncomplete) {
+                _tokenIncomplete = false;
+                _finishString(); // only strings can be incomplete
+            }
+            List<char[]> segments = _textBuffer.getCharacterSegments();
+
+            //Indicates the currently read text buffer index which refers to the 
+            //TextBuffer character segment
+            int readTextBufferIndex = 0;
+            //if there are character segments, then use them and write them to the writer
+            while(segments != null && readTextBufferIndex < segments.size()) {
+                writer.write(segments.get(readTextBufferIndex));
+                len += segments.get(readTextBufferIndex).length;
+                readTextBufferIndex++;
+            }
+            //if there are no character segments left, then read the string from the current segment, and 
+            //write them directly to the buffer
+            writer.write(_textBuffer.getCurrentSegment(), 0, _textBuffer.getCurrentSegmentSize());
+            len += _textBuffer.getCurrentSegmentSize();
+
+        }
+        else if(t != null) {
+            switch (t.id()) {
+            case ID_FIELD_NAME:
+                writer.write(_parsingContext.getCurrentName());
+                break;    
+            case ID_STRING:
+            case ID_NUMBER_INT:
+            case ID_NUMBER_FLOAT:
+                writer.write(_textBuffer.contentsAsString());
+                break;
+            default:
+                writer.write(t.asString());
+            }
+        }
+
+        return len;
+    }
 
     // // // Let's override default impls for improved performance
 

diff --git a/src/main/java/com/fasterxml/jackson/core/util/JsonParserDelegate.java b/src/main/java/com/fasterxml/jackson/core/util/JsonParserDelegate.java
@@ -2,6 +2,7 @@
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.io.Writer;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 
@@ -143,6 +144,7 @@ public JsonParser overrideFormatFeatures(int values, int mask) {
     @Override public char[] getTextCharacters() throws IOException { return delegate.getTextCharacters(); }
     @Override public int getTextLength() throws IOException { return delegate.getTextLength(); }
     @Override public int getTextOffset() throws IOException { return delegate.getTextOffset(); }
+    @Override public int readText(Writer writer) throws IOException, UnsupportedOperationException { return delegate.readText(writer);  }
 
     /*
     /**********************************************************

diff --git a/src/main/java/com/fasterxml/jackson/core/util/TextBuffer.java b/src/main/java/com/fasterxml/jackson/core/util/TextBuffer.java
@@ -3,6 +3,7 @@
 import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 
 import com.fasterxml.jackson.core.io.NumberInput;
 
@@ -506,6 +507,15 @@ public void append(String str, int offset, int len)
         } while (len > 0);
     }
 
+    /**
+     * Returns the raw list of character segments
+     * 
+     * @return The character segments
+     */
+     public List<char[]> getCharacterSegments() {
+         return _segments;
+     }
+
     /*
     /**********************************************************
     /* Raw access, for high-performance use:

diff --git a/src/test/java/com/fasterxml/jackson/core/read/JsonParserTest.java b/src/test/java/com/fasterxml/jackson/core/read/JsonParserTest.java
@@ -615,6 +615,90 @@ private void _testGetValueAsText(int mode, boolean delegate) throws Exception
         }
         p.close();
     }
+
+    public void testReadText() throws Exception {
+        final String JSON = "{\"a\":\"this is a sample text for json parsing using readText() method\",\"b\":true,\"c\":null,\"d\":\"foo\"}";
+        //create parser in reader mode..
+        JsonParser parser = createParser(MODE_READER, JSON);
+        //move the token until the string field
+        parser.nextToken();
+        parser.nextToken();
+        parser.nextToken();
+
+        Writer writer = new StringWriter();
+        int len = parser.readText(writer);
+
+        assertTrue("String length should be same", writer.toString().length() == "this is a sample text for json parsing using readText() method".length());
+        assertEquals("Returned length should be same", len, writer.toString().length());
+
+        //create parser in stream mode..
+        parser = createParser(MODE_INPUT_STREAM, JSON);
+        //move the token until the string field
+        parser.nextToken();
+        parser.nextToken();
+        parser.nextToken();
+
+        writer = new StringWriter();
+        len = parser.readText(writer);
+
+        assertTrue("String length should be same", writer.toString().length() == "this is a sample text for json parsing using readText() method".length());
+        assertEquals("Returned length should be same", len, writer.toString().length());
+
+        //create parser in data input mode..
+        parser = createParser(MODE_DATA_INPUT, JSON);
+        //move the token until the string field
+        parser.nextToken();
+        parser.nextToken();
+        parser.nextToken();
+
+        writer = new StringWriter();
+        len = parser.readText(writer);
+
+        assertTrue("String length should be same", writer.toString().length() == "this is a sample text for json parsing using readText() method".length());
+        assertEquals("Returned length should be same", len, writer.toString().length());
+    }
+
+    public void testLongerReadText() throws Exception {
+        StringBuilder builder = new StringBuilder();
+        for(int i= 0; i < 1000; i++) {
+            builder.append("Sample Text"+i);
+        }
+        String longText = builder.toString();
+        final String JSON = "{\"a\":\""+ longText +"\",\"b\":true,\"c\":null,\"d\":\"foo\"}";
+        //create parser in reader mode..
+        JsonParser parser = createParser(MODE_READER, JSON);
+        //move the token until the string field
+        parser.nextToken();
+        parser.nextToken();
+        parser.nextToken();
+
+        Writer writer = new StringWriter();
+        int len = parser.readText(writer);
+        assertEquals("Returned length should be same", len, writer.toString().length());
+
+        //create parser in stream mode..
+        parser = createParser(MODE_INPUT_STREAM, JSON);
+        //move the token until the string field
+        parser.nextToken();
+        parser.nextToken();
+        parser.nextToken();
+
+        writer = new StringWriter();
+        len = parser.readText(writer);
+        assertEquals("Returned length should be same", len, writer.toString().length());
+
+        //create parser in data input mode..
+        parser = createParser(MODE_DATA_INPUT, JSON);
+        //move the token until the string field
+        parser.nextToken();
+        parser.nextToken();
+        parser.nextToken();
+
+        writer = new StringWriter();
+        len = parser.readText(writer);
+        assertEquals("Returned length should be same", len, writer.toString().length());
+
+    }
 
     /*
     /**********************************************************