JsonElement.java

package com.google.gson;

import com.google.gson.internal.Streams;
import com.google.gson.stream.JsonWriter;
import java.io.IOException;
import java.io.StringWriter;

public abstract class JsonElement
{
  public boolean isJsonArray()
  {
    return this instanceof JsonArray;
  }

  public boolean isJsonObject()
  {
    return this instanceof JsonObject;
  }

  public boolean isJsonPrimitive()
  {
    return this instanceof JsonPrimitive;
  }

  public boolean isJsonNull()
  {
    return this instanceof JsonNull;
  }

  public JsonObject getAsJsonObject()
  {
    if (isJsonObject()) {
      return (JsonObject)this;
    }
    throw new IllegalStateException("Not a JSON Object: " + this);
  }

  public JsonArray getAsJsonArray()
  {
    if (isJsonArray()) {
      return (JsonArray)this;
    }
    throw new IllegalStateException("This is not a JSON Array.");
  }

  public JsonPrimitive getAsJsonPrimitive()
  {
    if (isJsonPrimitive()) {
      return (JsonPrimitive)this;
    }
    throw new IllegalStateException("This is not a JSON Primitive.");
  }

  public boolean getAsBoolean()
  {
    throw new UnsupportedOperationException(getClass().getSimpleName());
  }

  Boolean getAsBooleanWrapper()
  {
    throw new UnsupportedOperationException(getClass().getSimpleName());
  }

  public Number getAsNumber()
  {
    throw new UnsupportedOperationException(getClass().getSimpleName());
  }

  public String getAsString()
  {
    throw new UnsupportedOperationException(getClass().getSimpleName());
  }

  public double getAsDouble()
  {
    throw new UnsupportedOperationException(getClass().getSimpleName());
  }

  public long getAsLong()
  {
    throw new UnsupportedOperationException(getClass().getSimpleName());
  }

  public int getAsInt()
  {
    throw new UnsupportedOperationException(getClass().getSimpleName());
  }

  public String toString()
  {
    try
    {
      StringWriter stringWriter = new StringWriter();
      JsonWriter jsonWriter = new JsonWriter(stringWriter);
      jsonWriter.setLenient(true);
      Streams.write(this, jsonWriter);
      return stringWriter.toString();
    } catch (IOException e) {
      throw new AssertionError(e);
    }
  }
}