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我正在使用傑克遜1.9。在我的web應用程序中，我需要將複雜對象（如Spring的ModelMap，BindingResult，java.uil.Map）轉換爲JSON String對象。使用傑克遜1.9時的OutOfMemory
請考慮下面的代碼片段，我在嘗試這樣的一個轉換：
Map<String, Object> methodArgsMap = new HashMap<String, Object>();
methodArgsMap.put("map", map);/*map is an instance of org.springframework.ui.ModelMap*/
methodArgsMap.put("command", command);/*command is an instance of a custom POJO viz.ReportBeanParam*/
methodArgsMap.put("result", result);/*result is an instance of org.springframework.validation.BindingResult*/
的方法是JSONProcessUtil。爲實現getObjectsAsJSONString（...）如下：
public final class JSONProcessUtil {
private static ObjectMapper objectMapper;
static {
objectMapper = new ObjectMapper();
/*Start : Configs. suggested by Jackson docs to avoid OutOfMemoryError*/
SerializationConfig serConfig = objectMapper.getSerializationConfig();
serConfig.disable(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS);
objectMapper.getJsonFactory().configure(
JsonParser.Feature.INTERN_FIELD_NAMES, false);
objectMapper.getJsonFactory().configure(
JsonParser.Feature.CANONICALIZE_FIELD_NAMES, false);
/*End : Configs. suggested by Jackson docs to avoid OutOfMemoryError*/
}
public static Map<String, String> getObjectsAsJSONString(
Map<String, Object> argsMap) throws JsonGenerationException,
JsonMappingException, IOException {
log.info("Source app.In JSONProcessUtil.getObjectsAsJSONString(...)");
Map<String, String> jsonStrMap = null;
if (!(argsMap == null || argsMap.isEmpty())) {
jsonStrMap = new HashMap<String, String>();
Set<String> keySet = argsMap.keySet();
Iterator<String> iter = keySet.iterator();
String argName = null;
while (iter.hasNext()) {
argName = iter.next();
log.info("Source app. argName = {}, arg = {} ", argName,
argsMap.get(argName));
jsonStrMap.put(argName,
objectMapper.writeValueAsString(argsMap.get(argName)));/*The line giving error*/
log.info("Proceeding to the next arg !");
}
}
log.info("Source app. Exit from JSONProcessUtil.getObjectsAsJSONString(...)");
return jsonStrMap;
}
}
我正在一個的OutOfMemoryError如下：
INFO [http-8080-7] (JSONProcessUtil.java:73) - Source app. argName = result, arg = org.springframework.validation.BeanPropertyBindingResult: 0 errors DEBUG [http-8080-7] (SecurityContextPersistenceFilter.java:89) - SecurityContextHolder now cleared, as request processing completed Feb 20, 2012 5:03:30 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet saas threw exception
java.lang.OutOfMemoryError: Java heap space
at org.codehaus.jackson.util.TextBuffer._charArray(TextBuffer.java:
674)
at org.codehaus.jackson.util.TextBuffer.expand(TextBuffer.java:633)
at org.codehaus.jackson.util.TextBuffer.append(TextBuffer.java:438)
at org.codehaus.jackson.io.SegmentedStringWriter.write(SegmentedStringWriter.java:69)
at org.codehaus.jackson.impl.WriterBasedGenerator._flushBuffer(WriterBasedGenerator.java:1810)
at org.codehaus.jackson.impl.WriterBasedGenerator._writeFieldName(WriterBasedGenerator.java:345)
at org.codehaus.jackson.impl.WriterBasedGenerator.writeFieldName(WriterBasedGenerator.java:217)
at org.codehaus.jackson.map.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:426)
at org.codehaus.jackson.map.ser.BeanSerializer.serializeFields(BeanSerializer.java:175)
at org.codehaus.jackson.map.ser.BeanSerializer.serialize(BeanSerializer.java:142)
at org.codehaus.jackson.map.ser.impl.ObjectArraySerializer.serializeContents(ObjectArraySerializer.java:121)
at org.codehaus.jackson.map.ser.impl.ObjectArraySerializer.serializeContents(ObjectArraySerializer.java:28)
at org.codehaus.jackson.map.ser.ArraySerializers$AsArraySerializer.serialize(ArraySerializers.java:56)
at org.codehaus.jackson.map.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:428)
at org.codehaus.jackson.map.ser.BeanSerializer.serializeFields(BeanSerializer.java:175)
at org.codehaus.jackson.map.ser.BeanSerializer.serialize(BeanSerializer.java:142)
at org.codehaus.jackson.map.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:428)
at org.codehaus.jackson.map.ser.BeanSerializer.serializeFields(BeanSerializer.java:175)
at org.codehaus.jackson.map.ser.BeanSerializer.serialize(BeanSerializer.java:142)
at org.codehaus.jackson.map.ser.MapSerializer.serializeFields(MapSerializer.java:287)
at org.codehaus.jackson.map.ser.MapSerializer.serialize(MapSerializer.java:212)
at org.codehaus.jackson.map.ser.MapSerializer.serialize(MapSerializer.java:23)
at org.codehaus.jackson.map.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:428)
at org.codehaus.jackson.map.ser.BeanSerializer.serializeFields(BeanSerializer.java:175)
at org.codehaus.jackson.map.ser.BeanSerializer.serialize(BeanSerializer.java:142)
at org.codehaus.jackson.map.ser.MapSerializer.serializeFields(MapSerializer.java:287)
at org.codehaus.jackson.map.ser.MapSerializer.serialize(MapSerializer.java:212)
at org.codehaus.jackson.map.ser.MapSerializer.serialize(MapSerializer.java:23)
at org.codehaus.jackson.map.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:428)
at org.codehaus.jackson.map.ser.BeanSerializer.serializeFields(BeanSerializer.java:175)
at org.codehaus.jackson.map.ser.BeanSerializer.serialize(BeanSerializer.java:142)
at org.codehaus.jackson.map.ser.MapSerializer.serializeFields(MapSerializer.java:287)
請指導有關解決相同。
感謝和問候！