How to use

ExtractToNullCheckedLocalProposal$RearrangeStrategy$ModifyBlock

in

org.eclipse.jdt.internal.ui.text.correction.proposals

  @Override
  public void insertIfStatement(IfStatement ifStmt, Block thenBlock) {
    // when stmt declares a local variable (see RearrangeStrategy.create(..)) we need to move all
    // subsequent statements into the then-block to ensure that the existing declared local is visible:
    List<ASTNode> blockStmts= this.block.statements();
    int stmtIdx= blockStmts.indexOf(this.origStmt);
    int lastIdx= blockStmts.size()-1;
    if (stmtIdx != -1 && stmtIdx < lastIdx) {
      thenBlock.statements()
      .add(this.blockRewrite.createMoveTarget(blockStmts.get(stmtIdx+1), blockStmts.get(lastIdx), null, this.group));
    }
    super.insertIfStatement(ifStmt, thenBlock);
  }
}

public static RearrangeStrategy create(Statement origStmt, ASTRewrite rewrite, TextEditGroup group) {
  ASTNode parent = origStmt.getParent();
  if (parent instanceof Block) {
    Block block= (Block)parent;
    if (origStmt instanceof VariableDeclarationStatement)
      return new ModifyBlockWithLocalDecl(origStmt, block, rewrite, group);
    else
      return new ModifyBlock(origStmt, block, rewrite, group);
  } else {
    return new ReplaceStatement(origStmt, rewrite, group);
  }
}

public static RearrangeStrategy create(Statement origStmt, ASTRewrite rewrite, TextEditGroup group) {
  ASTNode parent = origStmt.getParent();
  if (parent instanceof Block) {
    Block block= (Block)parent;
    if (origStmt instanceof VariableDeclarationStatement)
      return new ModifyBlockWithLocalDecl(origStmt, block, rewrite, group);
    else
      return new ModifyBlock(origStmt, block, rewrite, group);
  } else {
    return new ReplaceStatement(origStmt, rewrite, group);
  }
}

  @Override
  public void insertIfStatement(IfStatement ifStmt, Block thenBlock) {
    // when stmt declares a local variable (see RearrangeStrategy.create(..)) we need to move all
    // subsequent statements into the then-block to ensure that the existing declared local is visible:
    List<ASTNode> blockStmts= this.block.statements();
    int stmtIdx= blockStmts.indexOf(this.origStmt);
    int lastIdx= blockStmts.size()-1;
    if (stmtIdx != -1 && stmtIdx < lastIdx) {
      thenBlock.statements()
      .add(this.blockRewrite.createMoveTarget(blockStmts.get(stmtIdx+1), blockStmts.get(lastIdx), null, this.group));
    }
    super.insertIfStatement(ifStmt, thenBlock);
  }
}