CodedInputStream

java.lang.Object
- com.google.protobuf.CodedInputStream

```
public final class CodedInputStream
extends java.lang.Object
```
Reads and decodes protocol message fields. This class contains two kinds of methods: methods that read specific protocol message constructs and field types (e.g. readTag() and readInt32()) and methods that read low-level values (e.g. readRawVarint32() and readRawBytes(int)). If you are reading encoded protocol messages, you should use the former methods, but if you are reading some other format of your own design, use the latter.

Author:

kenton@google.com Kenton Varda

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`checkLastTagWas(int value)` Verifies that the last call to readTag() returned the given tag value.
`static int`	`decodeZigZag32(int n)` Decode a ZigZag-encoded 32-bit value.
`static long`	`decodeZigZag64(long n)` Decode a ZigZag-encoded 64-bit value.
`int`	`getBytesUntilLimit()` Returns the number of bytes to be read before the current limit.
`int`	`getTotalBytesRead()` The total bytes read up to the current position.
`boolean`	`isAtEnd()` Returns true if the stream has reached the end of the input.
`static CodedInputStream`	`newInstance(byte[] buf)` Create a new CodedInputStream wrapping the given byte array.
`static CodedInputStream`	`newInstance(byte[] buf, int off, int len)` Create a new CodedInputStream wrapping the given byte array slice.
`static CodedInputStream`	`newInstance(java.io.InputStream input)` Create a new CodedInputStream wrapping the given InputStream.
`void`	`popLimit(int oldLimit)` Discards the current limit, returning to the previous limit.
`int`	`pushLimit(int byteLimit)` Sets `currentLimit` to (current position) + `byteLimit`.
`boolean`	`readBool()` Read a `bool` field value from the stream.
`ByteString`	`readBytes()` Read a `bytes` field value from the stream.
`double`	`readDouble()` Read a `double` field value from the stream.
`int`	`readEnum()` Read an enum field value from the stream.
`int`	`readFixed32()` Read a `fixed32` field value from the stream.
`long`	`readFixed64()` Read a `fixed64` field value from the stream.
`float`	`readFloat()` Read a `float` field value from the stream.
`void`	`readGroup(int fieldNumber, MessageLite.Builder builder, ExtensionRegistryLite extensionRegistry)` Read a `group` field value from the stream.
`<T extends MessageLite> T`	`readGroup(int fieldNumber, Parser<T> parser, ExtensionRegistryLite extensionRegistry)` Read a `group` field value from the stream.
`int`	`readInt32()` Read an `int32` field value from the stream.
`long`	`readInt64()` Read an `int64` field value from the stream.
`void`	`readMessage(MessageLite.Builder builder, ExtensionRegistryLite extensionRegistry)` Read an embedded message field value from the stream.
`<T extends MessageLite> T`	`readMessage(Parser<T> parser, ExtensionRegistryLite extensionRegistry)` Read an embedded message field value from the stream.
`byte`	`readRawByte()` Read one byte from the input.
`byte[]`	`readRawBytes(int size)` Read a fixed size of bytes from the input.
`int`	`readRawLittleEndian32()` Read a 32-bit little-endian integer from the stream.
`long`	`readRawLittleEndian64()` Read a 64-bit little-endian integer from the stream.
`int`	`readRawVarint32()` Read a raw Varint from the stream.
`static int`	`readRawVarint32(int firstByte, java.io.InputStream input)` Like `readRawVarint32(InputStream)`, but expects that the caller has already read one byte.
`long`	`readRawVarint64()` Read a raw Varint from the stream.
`int`	`readSFixed32()` Read an `sfixed32` field value from the stream.
`long`	`readSFixed64()` Read an `sfixed64` field value from the stream.
`int`	`readSInt32()` Read an `sint32` field value from the stream.
`long`	`readSInt64()` Read an `sint64` field value from the stream.
`java.lang.String`	`readString()` Read a `string` field value from the stream.
`int`	`readTag()` Attempt to read a field tag, returning zero if we have reached EOF.
`int`	`readUInt32()` Read a `uint32` field value from the stream.
`long`	`readUInt64()` Read a `uint64` field value from the stream.
`void`	`readUnknownGroup(int fieldNumber, MessageLite.Builder builder)` Deprecated. UnknownFieldSet.Builder now implements MessageLite.Builder, so you can just call `readGroup(int, com.google.protobuf.MessageLite.Builder, com.google.protobuf.ExtensionRegistryLite)`.
`void`	`resetSizeCounter()` Resets the current size counter to zero (see `setSizeLimit(int)`).
`int`	`setRecursionLimit(int limit)` Set the maximum message recursion depth.
`int`	`setSizeLimit(int limit)` Set the maximum message size.
`boolean`	`skipField(int tag)` Reads and discards a single field, given its tag value.
`void`	`skipMessage()` Reads and discards an entire message.
`void`	`skipRawBytes(int size)` Reads and discards `size` bytes.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - newInstance
```
public static CodedInputStream newInstance(java.io.InputStream input)
```
    Create a new CodedInputStream wrapping the given InputStream.
  - newInstance
```
public static CodedInputStream newInstance(byte[] buf)
```
    Create a new CodedInputStream wrapping the given byte array.
  - newInstance
```
public static CodedInputStream newInstance(byte[] buf,
                           int off,
                           int len)
```
    Create a new CodedInputStream wrapping the given byte array slice.
  - readTag
```
public int readTag()
            throws java.io.IOException
```
    Attempt to read a field tag, returning zero if we have reached EOF. Protocol message parsers use this to read tags, since a protocol message may legally end wherever a tag occurs, and zero is not a valid tag number.
    
    Throws:
    
    java.io.IOException
  - checkLastTagWas
```
public void checkLastTagWas(int value)
                     throws InvalidProtocolBufferException
```
    Verifies that the last call to readTag() returned the given tag value. This is used to verify that a nested group ended with the correct end tag.
    
    Throws:
    
    InvalidProtocolBufferException - value does not match the last tag.
  - skipField
```
public boolean skipField(int tag)
                  throws java.io.IOException
```
    Reads and discards a single field, given its tag value.
    
    Returns:
    false if the tag is an endgroup tag, in which case nothing is skipped. Otherwise, returns true.
    
    Throws:
    
    java.io.IOException
  - skipMessage
```
public void skipMessage()
                 throws java.io.IOException
```
    Reads and discards an entire message. This will read either until EOF or until an endgroup tag, whichever comes first.
    
    Throws:
    
    java.io.IOException
  - readDouble
```
public double readDouble()
                  throws java.io.IOException
```
    Read a double field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readFloat
```
public float readFloat()
                throws java.io.IOException
```
    Read a float field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readUInt64
```
public long readUInt64()
                throws java.io.IOException
```
    Read a uint64 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readInt64
```
public long readInt64()
               throws java.io.IOException
```
    Read an int64 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readInt32
```
public int readInt32()
              throws java.io.IOException
```
    Read an int32 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readFixed64
```
public long readFixed64()
                 throws java.io.IOException
```
    Read a fixed64 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readFixed32
```
public int readFixed32()
                throws java.io.IOException
```
    Read a fixed32 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readBool
```
public boolean readBool()
                 throws java.io.IOException
```
    Read a bool field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readString
```
public java.lang.String readString()
                            throws java.io.IOException
```
    Read a string field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readGroup
```
public void readGroup(int fieldNumber,
             MessageLite.Builder builder,
             ExtensionRegistryLite extensionRegistry)
               throws java.io.IOException
```
    Read a group field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readGroup
```
public <T extends MessageLite> T readGroup(int fieldNumber,
                                  Parser<T> parser,
                                  ExtensionRegistryLite extensionRegistry)
                                throws java.io.IOException
```
    Read a group field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readUnknownGroup
```
@Deprecated
public void readUnknownGroup(int fieldNumber,
                               MessageLite.Builder builder)
                      throws java.io.IOException
```
    Deprecated. UnknownFieldSet.Builder now implements MessageLite.Builder, so you can just call readGroup(int, com.google.protobuf.MessageLite.Builder, com.google.protobuf.ExtensionRegistryLite).
    
    Reads a group field value from the stream and merges it into the given UnknownFieldSet.
    
    Throws:
    
    java.io.IOException
  - readMessage
```
public void readMessage(MessageLite.Builder builder,
               ExtensionRegistryLite extensionRegistry)
                 throws java.io.IOException
```
    Read an embedded message field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readMessage
```
public <T extends MessageLite> T readMessage(Parser<T> parser,
                                    ExtensionRegistryLite extensionRegistry)
                                  throws java.io.IOException
```
    Read an embedded message field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readBytes
```
public ByteString readBytes()
                     throws java.io.IOException
```
    Read a bytes field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readUInt32
```
public int readUInt32()
               throws java.io.IOException
```
    Read a uint32 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readEnum
```
public int readEnum()
             throws java.io.IOException
```
    Read an enum field value from the stream. Caller is responsible for converting the numeric value to an actual enum.
    
    Throws:
    
    java.io.IOException
  - readSFixed32
```
public int readSFixed32()
                 throws java.io.IOException
```
    Read an sfixed32 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readSFixed64
```
public long readSFixed64()
                  throws java.io.IOException
```
    Read an sfixed64 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readSInt32
```
public int readSInt32()
               throws java.io.IOException
```
    Read an sint32 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readSInt64
```
public long readSInt64()
                throws java.io.IOException
```
    Read an sint64 field value from the stream.
    
    Throws:
    
    java.io.IOException
  - readRawVarint32
```
public int readRawVarint32()
                    throws java.io.IOException
```
    Read a raw Varint from the stream. If larger than 32 bits, discard the upper bits.
    
    Throws:
    
    java.io.IOException
  - readRawVarint32
```
public static int readRawVarint32(int firstByte,
                  java.io.InputStream input)
                           throws java.io.IOException
```
    Like readRawVarint32(InputStream), but expects that the caller has already read one byte. This allows the caller to determine if EOF has been reached before attempting to read.
    
    Throws:
    
    java.io.IOException
  - readRawVarint64
```
public long readRawVarint64()
                     throws java.io.IOException
```
    Read a raw Varint from the stream.
    
    Throws:
    
    java.io.IOException
  - readRawLittleEndian32
```
public int readRawLittleEndian32()
                          throws java.io.IOException
```
    Read a 32-bit little-endian integer from the stream.
    
    Throws:
    
    java.io.IOException
  - readRawLittleEndian64
```
public long readRawLittleEndian64()
                           throws java.io.IOException
```
    Read a 64-bit little-endian integer from the stream.
    
    Throws:
    
    java.io.IOException
  - decodeZigZag32
```
public static int decodeZigZag32(int n)
```
    Decode a ZigZag-encoded 32-bit value. ZigZag encodes signed integers into values that can be efficiently encoded with varint. (Otherwise, negative values must be sign-extended to 64 bits to be varint encoded, thus always taking 10 bytes on the wire.)
    
    Parameters:
    n - An unsigned 32-bit integer, stored in a signed int because Java has no explicit unsigned support.
    
    Returns:
    A signed 32-bit integer.
  - decodeZigZag64
```
public static long decodeZigZag64(long n)
```
    Decode a ZigZag-encoded 64-bit value. ZigZag encodes signed integers into values that can be efficiently encoded with varint. (Otherwise, negative values must be sign-extended to 64 bits to be varint encoded, thus always taking 10 bytes on the wire.)
    
    Parameters:
    n - An unsigned 64-bit integer, stored in a signed int because Java has no explicit unsigned support.
    
    Returns:
    A signed 64-bit integer.
  - setRecursionLimit
```
public int setRecursionLimit(int limit)
```
    Set the maximum message recursion depth. In order to prevent malicious messages from causing stack overflows, CodedInputStream limits how deeply messages may be nested. The default limit is 64.
    
    Returns:
    the old limit.
  - setSizeLimit
```
public int setSizeLimit(int limit)
```
    Set the maximum message size. In order to prevent malicious messages from exhausting memory or causing integer overflows, CodedInputStream limits how large a message may be. The default limit is 64MB. You should set this limit as small as you can without harming your app's functionality. Note that size limits only apply when reading from an InputStream, not when constructed around a raw byte array (nor with ByteString.newCodedInput()).
    If you want to read several messages from a single CodedInputStream, you could call resetSizeCounter() after each one to avoid hitting the size limit.
    
    Returns:
    the old limit.
  - resetSizeCounter
```
public void resetSizeCounter()
```
    Resets the current size counter to zero (see setSizeLimit(int)).
  - pushLimit
```
public int pushLimit(int byteLimit)
              throws InvalidProtocolBufferException
```
    Sets currentLimit to (current position) + byteLimit. This is called when descending into a length-delimited embedded message.
    Note that pushLimit() does NOT affect how many bytes the CodedInputStream reads from an underlying InputStream when refreshing its buffer. If you need to prevent reading past a certain point in the underlying InputStream (e.g. because you expect it to contain more data after the end of the message which you need to handle differently) then you must place a wrapper around your InputStream which limits the amount of data that can be read from it.
    
    Returns:
    the old limit.
    
    Throws:
    
    InvalidProtocolBufferException
  - popLimit
```
public void popLimit(int oldLimit)
```
    Discards the current limit, returning to the previous limit.
    
    Parameters:
    oldLimit - The old limit, as returned by pushLimit.
  - getBytesUntilLimit
```
public int getBytesUntilLimit()
```
    Returns the number of bytes to be read before the current limit. If no limit is set, returns -1.
  - isAtEnd
```
public boolean isAtEnd()
                throws java.io.IOException
```
    Returns true if the stream has reached the end of the input. This is the case if either the end of the underlying input source has been reached or if the stream has reached a limit created using pushLimit(int).
    
    Throws:
    
    java.io.IOException
  - getTotalBytesRead
```
public int getTotalBytesRead()
```
    The total bytes read up to the current position. Calling resetSizeCounter() resets this value to zero.
  - readRawByte
```
public byte readRawByte()
                 throws java.io.IOException
```
    Read one byte from the input.
    
    Throws:
    
    InvalidProtocolBufferException - The end of the stream or the current limit was reached.
    
    java.io.IOException
  - readRawBytes
```
public byte[] readRawBytes(int size)
                    throws java.io.IOException
```
    Read a fixed size of bytes from the input.
    
    Throws:
    
    InvalidProtocolBufferException - The end of the stream or the current limit was reached.
    
    java.io.IOException
  - skipRawBytes
```
public void skipRawBytes(int size)
                  throws java.io.IOException
```
    Reads and discards size bytes.
    
    Throws:
    
    InvalidProtocolBufferException - The end of the stream or the current limit was reached.
    
    java.io.IOException

Class CodedInputStream

Method Summary

Methods inherited from class java.lang.Object

Method Detail

newInstance

newInstance

newInstance

readTag

checkLastTagWas

skipField

skipMessage

readDouble

readFloat

readUInt64

readInt64

readInt32

readFixed64

readFixed32

readBool

readString

readGroup

readGroup

readUnknownGroup

readMessage

readMessage

readBytes

readUInt32

readEnum

readSFixed32

readSFixed64

readSInt32

readSInt64

readRawVarint32

readRawVarint32

readRawVarint64

readRawLittleEndian32

readRawLittleEndian64

decodeZigZag32

decodeZigZag64

setRecursionLimit

setSizeLimit

resetSizeCounter

pushLimit

popLimit

getBytesUntilLimit

isAtEnd

getTotalBytesRead

readRawByte

readRawBytes

skipRawBytes