com.fasterxml.jackson.core.JsonToken#isStructStart ( )源码实例Demo

/**
 * Iterates through the JSON structure and collects weather data.
 */
private void handleToken(JsonParser jp, String property, Weather weather) throws Exception {
    JsonToken token = jp.getCurrentToken();
    String prop = PropertyResolver.add(property, jp.getCurrentName());

    if (token.isStructStart()) {
        boolean isObject = token == JsonToken.START_OBJECT || token == JsonToken.END_OBJECT;

        Weather forecast = !isObject ? weather : startIfForecast(weather, prop);
        while (!jp.nextValue().isStructEnd()) {
            handleToken(jp, prop, forecast);
        }
        if (isObject) {
            endIfForecast(weather, forecast, prop);
        }
    } else {
        try {
            setValue(weather, prop, jp.getValueAsString());
        } catch (Exception ex) {
            logger.error("Error setting property '{}' with value '{}' ({})", prop, jp.getValueAsString(),
                    ex.getMessage());
        }
    }
}
 

/**
 * Helper used to skip to the end of the current object.  Useful for forwards compatibility.
 *
 * @param jparser The parser to use for extraction.
 * @throws IOException If there is an error parsing.
 */
protected void ignoreRestOfObject(JsonParser jparser)
        throws IOException
{
    if (jparser.getCurrentToken().isStructEnd()) {
        return;
    }

    int open = 1;
    /* Since proper matching of start/end markers is handled
     * by nextToken(), we'll just count nesting levels here
     */
    while (true) {
        JsonToken t = jparser.nextToken();
        if (t == null) {
            throw new IllegalStateException("Expected " + JsonToken.END_OBJECT + " found " + jparser.getText());
        }
        if (t.isStructStart()) {
            ++open;
        }
        else if (t.isStructEnd()) {
            if (--open == 0) {
                return;
            }
        }
    }
}
 

private int nestingOffset(JsonToken t) {
    if (t.isStructStart()) {
        return 1;
    } else if (t.isStructEnd()) {
        return -1;
    } else {
        return 0;
    }
}
 

private boolean needsAcknowledgement(JsonParser parser) throws IOException{
    boolean acknowledge = false;
    boolean readAcknowledge = false;

    int open = 1;
    while(true){
        JsonToken t = parser.nextToken();
        if(readAcknowledge){
            readAcknowledge = false;
            if(t==JsonToken.VALUE_TRUE)
                acknowledge = true;
            else if(t==JsonToken.VALUE_FALSE)
                acknowledge = false;
        }

        if(t==null)
            throw new JsonParseException("unexpected EOF", parser.getCurrentLocation());
        else if(t.isStructStart())
            open++;
        else if(t.isStructEnd()){
            if(--open==0)
                return acknowledge;
        }else if(open==1 && t==JsonToken.FIELD_NAME && parser.getText().equals("acknowledge")){
            readAcknowledge = true;
        }
    }
}
 

/**
 * Skips a field name if necessary, returning the current token then, which must be
 * the start of an Array or Object: '{' or '['.
 */
public static JsonToken peekStructStart(JsonParser par) throws IOException {
  JsonToken token = peekToken(par);
  if (token.isStructStart()) {
    return token;
  } else {
    throw new JsonParseException(par, "Expected start of array or object");
  }
}
 

/** {@inheritDoc} */
@Override public String deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
    JsonToken startTok = p.getCurrentToken();

    if (startTok.isStructStart()) {
        StringWriter wrt = new StringWriter(4096);

        JsonGenerator gen = factory.createGenerator(wrt);

        JsonToken tok = startTok, endTok = startTok == START_ARRAY ? END_ARRAY : END_OBJECT;

        int cnt = 1;

        while (cnt > 0) {
            writeToken(tok, p, gen);

            tok = p.nextToken();

            if (tok == startTok)
                cnt++;
            else if (tok == endTok)
                cnt--;
        }

        gen.close();

        return wrt.toString();
    }

    return p.getValueAsString();
}